# Previous Experimental Particle Physics Seminars

2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002, 2001, 2000, 1999, 1998, and 1997
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Seminars in 2021
Wednesday March 17 2021 at 4pm
Jonathan Asaadi (University of Texas Arlington)
Q-Pix: Pixelated readout of kiloton scale noble element time projection chambers
Future long baseline neutrino experiments such as the Deep Underground Neutrino Experiment (DUNE) call for the deployment of multiple multi-kiloton scale liquid argon time projection chambers (LArTPCs). To date, two detector readout technologies are being studied in large-scale prototype detectors: the single phase (SP) and dual phase (DP) detectors using projective charge readout wire based anode planes. These projective readout technologies come with a set of challenges in the construction of the anode planes, the continuous readout of the system required to accomplish the physics goals of proton decay searches and supernova neutrino sensitivity, and the 2D projective reconstruction of complex neutrino topologies. The Q-Pix concept (
arXiv: 1809.10213) is a continuously integrating low-power charge-sensitive amplifier (CSA) viewed by a Schmitt trigger. When the trigger threshold is met, the comparator initiates a ‘reset’ transition and returns the CSA circuitry to a stable baseline. This is the elementary Charge-Integrate / Reset (CIR) circuit. The instance of reset time is captured in a 32-bit clock value register, buffers the cycle and then begins again. What is exploited in this new architecture is the time difference between one clock capture and the next sequential capture, called the Reset Time Difference (RTD). The RTD measures the time to integrate a predefined integrated quantum of charge (Q). Waveforms are reconstructed without differentiation and an event is characterized by the sequence of RTDs. In quiescent mode the RTDs will be evenly spaced with time intervals of seconds between RTDs with an event signaled by the appearance of a sequence of varying $\mu$s RTDs. This technique easily distinguishes the background RTDs due to 39Ar decays (which also provide an automatic absolute charge calibration) and signal RTD sequences due to ionizing tracks. Q-Pix offers the ability to extract all track information providing very detailed track profiles and also utilizes a dynamically established network for DAQ for exceptional resilience against single point failures. A number of novel ideas could be pursued to allow the Q-Pix design to be an integrated tracking/photo-detector. One such more speculative notion is the exploration of coating the dielectric surface with a type of photo-conductor which would respond to the VUV light incident on the surface. When struck by a VUV photon, the photoconductor would have electrons elevated into the conduction band and move in the electric field toward a pixel button. Initial R&D and simulation work on the Q-Pix concept will be presented in this work.
Wednesday April 14 2021 at **4pm**
Nedaa Alexandra Asbah (Harvard)
Evidence of the four-top-quark production at the LHC
A summary of the latest results on the evidence of the four-top-quark production using proton-proton collision data at a centre of-mass energy of 13 TeV collected by the ATLAS detector at the Large Hadron Collider with an integrated luminosity of 139 fb−1. Events are selected if they contain a same-sign lepton (electron or a muon) pair or at least three leptons (2lSS/3l) or a single lepton or an opposite-sign lepton pair (1l/2lOS). A multivariate technique is used to discriminate between signal and background events in the signal rich regions. The combined four top-quark production cross section is measured to be 24 +7/−6 fb, with a corresponding observed (expected) signal significance of 4.7 (2.6) standard deviations over the background-only predictions. It is consistent within 2.0 standard deviations with the Standard Model expectation of 12.0 ± 2.4 fb.
Seminars in 2020
Tuesday January 14 2020 at 2pm in 2C6
Ben Nachman (LBNL)
Deep Learning, Quantum Information, and the LHC as a Gluon Factory
Jets produced from high-energy quarks and gluons are ubiquitous at the Large Hadron Collider (LHC). These objects can be used to study emergent quantum properties of the strong force as well as search for new particles and forces beyond the Standard Model. As a jet can have O(100) particles, analyzing jets is inherently a high-dimensional problem. Therefore, jet physics has been leading the integration and development of modern machine learning tools for high-energy physics. This high dimensionality also is a challenge for classical techniques to account for all quantum effects in the evolution of jet formation. I will start by discussing the exciting new field of precision jet substructure, with the latest results from the ATLAS experiment and interpreted in the context of new theory calculations. This sets the stage for two exciting parallel developments where quantum computers and machine learning may lead to fundamentally new insights. After briefly mentioning the potential of quantum algorithms, I will illustrate the power of deep learning with a new class of algorithms called weak supervision that can learn directly from (unlabeled) data and potentially uncover high dimensional structures hidden from our ordinary three-dimensional view. In this way, machine learning can help us learn something new and fundamental about nature.
Monday February 10 2020 Joint Theory & Experiment Seminar
Nathaniel Craig (University of California, Santa Barbara)
See
recent papers

Wednesday October 28 2020 at 4pm
Tova Holmes (University of Tennessee)
Off the Beaten Track: Long-Lived Particles at the LHC
The LHC has reached a new era: nearly a decade without any large jumps in energy or luminosity. For those interested in finding Beyond the Standard Model (BSM) physics, a paradigm shift is required. In my talk I’ll discuss a search program looking for long-lived particles, which often escape detection from standard BSM searches, due to the difficulty of triggering on and reconstructing their unconventional signatures. These challenges result in a long-lived particle landscape full of unexcluded territory, opening up opportunities to find TeV-scale Supersymmetry, hidden sectors, right-handed neutrinos, and more. My talk will focus on the challenge of triggering in these searches, and how we can expand our capability to explore these new signatures.
Wednesday November 18 2020 at 4pm
Stephanie Majewski (University of Oregon)
Searching for the Supersymmetric Partner to the Top Quark at ATLAS: Don't Stop Believin'
The discovery of the stop — the Supersymmetric partner of the top quark — is a key goal of the ATLAS physics program enabled by the Large Hadron Collider. I will review the status of the search for direct stop pair production, focusing on stop decays via a hadronically decaying top quark and the lightest Supersymmetric particle (a compelling dark matter candidate). I will also discuss recent developments in the natural "stealth stop" regime, where the stop is nearly degenerate with the top quark, which is characterized by decay kinematics that force the final state top quark off its mass shell. Our recast of the ATLAS top mass measurements revealed that stop decays in this regime could contaminate the measurement of the top mass by up to 2 GeV. Thus, a robust statement on the exclusion of a stealth stop requires the simultaneous consideration of the impact on the top mass.
Wednesday December 2 2020 at 4pm
Louise Skinnari (Northeastern University)
Track-triggering at CMS for the High-Luminosity LHC
The high luminosity upgrade of the Large Hadron Collider (LHC), scheduled for 2025-2027, will significantly increase the instantaneous luminosity of the LHC collisions. The resulting large proton-proton collision datasets will allow precise measurements of Higgs boson properties, searches for very rare processes, and much more. To cope with the challenging experimental environment resulting from the high luminosity, significant upgrades will be required for the LHC detectors. A key upgrade of the CMS detector is to incorporate the identification of charged particle trajectories in the hardware-based trigger system, with potential to not only solidify the CMS trigger strategy but to enable searches for completely new physics signatures. This seminar will discuss the motivation of the CMS track trigger, give an overview of the system, and discuss its expected performance based on simulation and hardware demonstration.
Seminars in 2019
Wednesday February 6 2019 at 4:00pm in room A8
Elena Guardincerri (LANL)
Muon Radiography at the Los Alamos National Laboratory and Brunelleschi's dome in Florence
Cosmic-ray muons are free, ubiquitous, very penetrating particles. Muon radiography takes advantage of them to probe objects that, because of their thickness or the shielding around them, would be out of the reach of more traditional radiographic techniques. I will briefly review the different techniques that are currently used to perform cosmic-ray muon radiography and discuss some applications to actual problems. I will discuss, in particular, the use of cosmic ray muons to assess the content of dry casks containing spent nuclear fuel, an important task to maintain continuity of knowledge over the fuel itself and avoid its diversion. I will then show how muon induced neutron emission can be used to image high Z materials. Lastly I will discuss the use of cosmic ray muons to image the interior of thick walls for historic preservation purposes and our plans to image the interior wall of the cathedral of Florence, Italy
**Tuesday February 19 2019 at 1:30pm in room 4N12**
Shaomin Chen (Tsinghua University)
Jinping Neutrino Experiment

**Tuesday March 12 2019 at 1:30pm in room 4N12**
Boris Kayser (Fermilab)
Addressing the Majorana vs. Dirac Question Using Neutrino Decays

Wednesday March 20 2019 at 4:00pm in room A8
Kate Scholberg (Duke)
Coherent neutrino scattering

Wednesday April 3 2019 at 4:00pm in room A8
Richie Bonventre (LBNL)
Searching for muon to electron conversion: The Mu2e experiment at Fermilab
The Mu2e experiment will measure the charged-lepton flavor violating (CLFV) neutrino-less conversion of a negative muon into an electron in the field of a nucleus. Mu2e will improve the previous measurement by four orders of magnitude, reaching a 90% C.L. sensitivity to CLFV conversion rates of 8x10^-17 or larger. The experiment will reach mass scales of nearly 10^4 TeV, far beyond the direct reach of colliders. It will be sensitive to a wide range of new physics, complementing and extending other CLFV searches. Mu2e is under design and construction at the Muon Campus of Fermilab, and we expect to start taking physics data in 2023. I will present the physics motivation for Mu2e, the detector design, and the current experimental status.
Wednesday May 8 2019 at 10:00am in room A4
Brian Beckford (Michigan)
Latest results from KOTO

Thursday May 9 2019 at 1:30pm in room 2C8
Tomohiro Yamazaki (Tokyo)
Search for the supersymmetric partner of the top quark with the ATLAS detector
Supersymmetry (SUSY) is one of the promising extensions of the Standard Model that provides a solution to the hierarchy problem. Natural SUSY favors a scenario where a supersymmetric partner of the top quark (stop) has a mass light enough to be produced at the LHC, and the stop subsequently decays into higgsinos, supersymmetric partner of the Higgs bosons, as the lightest supersymmetric particle (LSP). In the compressed stop scenario where the stop mass is close to the LSP mass, the identification and reconstruction of low-pt b-hadrons are crucial. In this talk, the latest result of the stop (to higgsino) search is presented together with the recent development of a new b-tagging technique targeting the low-pt b-hadrons.
Wednesday October 9 2019 at 3pm in A4
Max Swiatlowski (TRIUMF)
Searching With di-Higgs Final States at ATLAS: A Window to the Standard Model and Beyond
The discovery of the Higgs boson has been a triumph for the Large Hadron Collider's physics program, but many open questions remain about this mysterious particle. Why is the Higgs mass so many orders of magnitude lower than the straightforward prediction? Can we observe the shape of the Higgs potential which gives rise to the particle, and can this potential be related to cosmological inflation or baryogenesis? Final states with two Higgs bosons, though extremely rare, can provide answers to these questions and more. I will present new ATLAS results for searches for direct di-Higgs production, including full run 2 results in the vector boson fusion production mode, as well as searches for electroweak supersymmetry involving decays to pairs of Higgs bosons. These searches employ several key innovations, such as the use of b-jet triggers and Boosted Decision Trees in background estimation, to achieve some of the strongest sensitivities yet to di-Higgs production and provide new insights into the nature of the Higgs.
Monday October 21 2019 at 3pm in A4 Joint Theory & Experiment Seminar
Patrick Meade (SUNY Stony Brook)
See
recent papers

Wednesday October 30 2019 at 3pm in room 4C2
Stefano Zambito (Harvard University)
Hunting for Supersymmetry at the LHC A Dive into Naturalness... And Beyond
After the discovery of the Higgs Boson, the predictions of the Standard Model of particle physics can be extrapolated without inconsistencies all the way up to the Planck mass. Despite this tremendous success, we still remain in the dark about many open puzzles. Why is the weak interaction much stronger than gravity? What is the nature of Dark Matter? Are the strong, weak and electromagnetic forces a lower-energy manifestation of one single fundamental interaction? A possible solution to these questions is provided by Supersymmetry. The key assumption behind many natural supersymmetric models is that the masses of the gluinos, the top squarks and the higgsinos are near the TeV scale, thus within the LHC reach. In this presentation, I will introduce some of the theoretical and phenomenological arguments that motivate the quest for Supersymmetry. I will then outline how I searched for the above-mentioned particles using LHC Run-2 data collected by the ATLAS experiment. Finally, I will focus on my vision of the future and my research plans in high-energy experimental physics.
Friday November 1 2019 at 2pm in room 3W2
Chunhui Chen (Iowa State University)
Higgs Boson decay as a probe to new physics beyond the standard model
Despite being a remarkably simple theoretical model, the Higgs mechanism is the only known theory that is connected to some of the most profound mysteries in the modern physics: dark energy, dark matter and missing antimatter. Measurements of the Higgs boson decay may shed light on those open questions. In this talk, I will present a few selective results from the ATLAS experiment on the Higgs boson decays. Namely the first observation of the Higgs boson decay to a pair of b-quarks, which had eluded us for many years despite it being the most probable Higgs decay channel; novel techniques to search for potential new physics using the hardonically decaying Higgs boson, and a first search for singly produced long-lived neutral particle that may be realized via Higgs portal. The talk will mainly focus on general descriptions of the measurements without too much technical details, so that the content is accessible to non experimental collider physicists.
Monday November 4 2019 at 3pm in A4 Joint Theory & Experiment Seminar
Andre de Gouvea (Northwestern University)
See recent papers

Wednesday November 6 2019 at 3pm in 4C2
Yongbin Feng (University of Maryland)
Search for emerging jets and other long-lived states with the CMS experiment
Many proposed extensions of the Standard Model contain particles with long lifetimes. When produced at the Large Hadron Collider (LHC) at CERN, these long-lived particles can produce displaced vertices and other non-conventional signatures. In this talk, I will present some recent results from searches for long-lived particles obtained using data collected by the CMS experiment at Run-II of the LHC. I will focus in particular on a model called “dark QCD” with “emerging jet” signatures.
Wednesday November 20 2019 at 3pm in 4C2
Christopher Palmer (Princeton University)
Observation of the Higgs boson decaying to bottom quarks at CMS
The Higgs boson decay to a bottom quark-antiquark pair has been sought for decades by the high energy community (i.e. at LEP and Tevatron). LHC experiments built analyses based on the experience of Tevatron experiments' analysis techniques. With the observation of the Higgs boson at LHC during Run 1, the search for this decay channel became sharply focused. As the bottom quark pair channel is the most probable decay of the Higgs boson (58%), its observation is both important in terms of quantifying the Higgs boson and it represents an important milestone in high energy physics. The results presented use datasets from the LHC Run 1 and Run 2 (2016+2017) from CMS. This Run 2, 13 TeV dataset corresponds to an integrated luminosity of ~80 fb^-1. The analysis strategy, the background estimation techniques, and significant analysis improvements from the 2017 data analysis in CMS are shown. An outlook on the upcoming analysis of the full Run 2 dataset (and beyond) will be discussed.
Seminars in 2018
Wednesday January 24 2018 at 4:00pm
Mark Vagins, University of Tokyo
Zen and the Art of Gadolinium-Loaded Water Cherenkov Detectors
Water Cherenkov detectors have been used for many years to study neutrino interactions and search for nucleon decays. Super-Kamiokande, at 50 kilotons the largest such underground detector in the world, has itself enjoyed over two decades of interesting and important physics results. Looking to the future, for the last fifteen years extensive R&D on a potential upgrade to the detector known as GADZOOKS! has been underway and is now complete; the project has been formally approved, and the detector will be prepared for Gd loading starting this summer. The benefits and challenges of enriching Super-K with 100,000 kilograms of a water-soluble gadolinium compound - thereby enabling it to detect thermal neutrons and dramatically improving its performance as a detector for supernova neutrinos, reactor neutrinos, atmospheric neutrinos, and also as a target for the T2K long-baseline neutrino experiment - will be discussed.
April 10 2018
Michael Ramsey-Musolf (UMass Amherst)
TeV Scale Lepton Number Violation: Neutrinoless Double Beta Decay & the LHC
Joint seminar with Theory
Tuesday August 7 2018 at 1:30pm in room 2C4
Lawrence Lee (Harvard University)
Searches for Supersymmetry with ATLAS

Monday August 27 2018 at 1:00pm in room 3W2
Sarah Williams (University of Cambridge)
Exploring the landscape of electroweak supersymmetry at the LHC: a quest for a better understanding of dark matter

Thursday September 27 2018 at 3:00pm in room 3C8
Soo-Bong Kim (Seoul National University)
Anomaly of Dancing Reactor Antineutrinos
The Reactor Experiment for Neutrino Oscillation(RENO) started data-taking from August, 2011 and has observed the disappearance of reactor electron antineutrinos to measure the smallest neutrino mixing angle theta13. The experiment has analyzed roughly 2200 days of data to make an accurate measurement of the oscillation amplitude and frequency based on energy and baseline dependent disappearance of reactor antineutrinos. RENO’s precisely measured flux and spectral shape of reactor antineutrinos has shown a deficit in the flux and an excess in the region of 5 MeV relative to the most commonly used model. Furthermore, it has observed fuel-composition dependent variation of reactor antineutrino yield and spectrum. We find that reevaluation of 235U’s antineutrino yield per fission may mostly solve the reactor antineutrino anomaly. We also report a hint of correlation between the 5-MeV excess and the 235U fuel isotope fraction.
Wednesday October 17 2018 at 4:00pm in room 2C2
Shirley Li (SLAC)
Solar neutrino sensitivity of DUNE

Wednesday October 24 2018 at 4:00pm in room A8
Alysia Marino (University of Colorado Boulder)
Recent results from T2K

Wednesday November 7 2018 at 4:00pm in room A8
Or Hen (MIT)
Short-range correlation studies in nuclei

Monday December 10 2018 at 2:30pm in room 4N12
Danielle Norcini (Yale)
First results from the PROSPECT reactor neutrino experiment
Experiments at nuclear reactors have played a key role in determining the properties of the weakly-interacting neutrinos. Results from recent reactor experiments suggest a disagreement between the observed antineutrino flux and energy spectrum when compared to predictions. Beyond the Standard Model sterile neutrinos and corrections to complex nuclear models have been posed to explain the discrepancy. To address this physics, the PROSPECT experiment precisely measures antineutrino energy spectra at multiple, very short baselines (< 10m) from the High Flux Isotope Reactor. This talk details the first sterile neutrino oscillation search and measurement of the uranium-235 antineutrino spectrum from PROSPECT.
Seminars in 2017
Tuesday September 19 2017 at 1:30pm
Shih-Chieh Hsu, University of Washington
Hunting for Dark Matter with Boosted Higgs Bosons in ATLAS
Although dark matter (DM) contributes a large component of the mass-energy of the universe, its properties and interactions with known particles remain unknown. In light of this unsolved puzzle, searches for DM pair-produced at Large Hadron Collider (LHC) provide important information complementary to direct and indirect searches in order to determine whether a signal observed experimentally indeed stems from DM. In this presentation, I will report the latest search results of DM pair production in association with a Higgs boson using the LHC Run2 data (sqrt(s)=13 TeV) collected by the ATLAS detector. I'll demonstrate the improvement of the analysis using the state-of-the-art boosted Higgs boson techniques. Because the observed data are found to be consistent with the expected Standard Model backgrounds, I'll show results interpreted using Z'-2HDM simplified models with the most stringent limits. Finally, I will discuss the prospects of this search in the coming LHC Run2 and new ideas of the boosted Higgs tagging.

Tuesday February 21 2017 at 1:30pm in 2C8
Jorge Chaves, Cornell
Search for right-handed W and heavy neutrinos in the 2l+2j final state at CMS
Despite the discovery of the standard model (SM) Higgs boson, there are still unanswered questions that are not explained by the SM, such as the nature of the chiral structure of weak interactions. During Run-1 at the LHC, no clear signs for physics beyond the SM were seen, but there were a few hints of possible new physics. One particular hint was a 2.8\sigma excess seen at the CMS experiment in the search for a heavy right-handed W and heavy neutrino. These particles arise when a left-right symmetry is added to the electroweak sector. In this seminar, I will discuss the Run-1 excess and show preliminary results from the current search with CMS at 13 TeV for a right-handed W in the two leptons plus two jets final state. Additionally, I will discuss the high-luminosity upgrade of the CMS tracker focusing on a proposed track-trigger system to be realized using FPGA technology.

### Seminars in 2016

Tuesday December 20 2016 at 1:30pm in 4C8
Shion Chen, University of Tokyo
Quest for gauginos in LHC-Run2 / ATLAS
Despite no significant beyond-the-standard model signatures has been observed in LHC Run1, the discovery of standard model higgs brought a substantial impact on supersymmetry search. As typical minimal models naively need O(10TeV) light flavor sfermions to reconcile with the 125 GeV higgs, there is a grown motivation in searching gauginos which are almost free from the higgs mass constraint. Gluino is in particular an interesting target in early Run2 as the production cross-section greatly enhanced by the doubled center-of-mass energy, and the status is quickly evolving along luminosity. Searching EWKinos, especially for realistic scenarios where the mass spectra is compressed, has more challenges due to their low production cross-section, poor S/N and trigger issue etc., however these are starting to be overcome by recent effort and emerging large data statistics of Run2 and later. This talk will cover the status-quo and prospect of both searches in the ATLAS experiment, with particular focus on (1) up-to-date analysis of gluino search in 1-lepton final state, and (2) R&D studies on multi-variate techniques for the compressed spectra analysis of EWKino search.

Tuesday December 13 2016 at 1:30pm in 4C8
Alessandro Tricoli, Brookhaven National Laboratory
A new era of precision physics with di-bosons at the LHC
The Run-2 of the LHC has opened up a new window on precision physics measurements. Thanks to higher cross sections of physics processes at 13 TeV compared to 7 and 8 TeV centre-of-mass energies, the increasing amount of data being collected and sophisticated experimental techniques, we can reach high precisions on measurements of properties of rare processes such as the production cross sections of two massive electroweak gauge bosons, for example two W bosons. LHC results on di-boson production cross sections at different centre-of-mass energies constitute stringent tests of both the strong and the electroweak sectors of the Standard Model and provide a model-independent mean to search for new physics at high energy scales. The high experimental precision recently achieved in several Run-1 measurements at the LHC together with hints of discrepancies observed between some di-boson measurements and Standard Model predictions have prompted significant progress in calculations at high orders in perturbation theory. This global effort has led in the past months to the so-called "next-to-next-to-leading order revolution", i.e. and explosion of new calculations that can reach percent level precision in the calculation of several processes including di-boson production cross sections. We are indeed on the threshold of a new era of precision physics for di-boson production at the multi-TeV energy scales. This seminar will focus on recent measurements of inclusive and differential cross sections for WW production at centre of mass energies of 13 TeV and 8 TeV by the ATLAS Collaboration at the LHC.

Tuesday December 6 2016 at 1:30pm in 4C8
Allison McCarn, University of Michigan
Searches for New Physics Through Third Generation Particles at the ATLAS Detector
The Standard Model (SM) has been central to particle physics for decades, and its success in predicting observational results has culminated in the 2012 discovery of a Higgs boson at the Large Hadron Collider. However, the theory is considered ‘not natural’, requiring finely-tuned parameters to allow for the precise cancellation of large radiative corrections to the Higgs boson mass. In pursuit of a more natural theory, extensions to the SM have been proposed that would stabilize the Higgs boson mass and resolve the hierarchy problem (supersymmetry, extended Higgs sectors, models with vector-like quarks). This presentation will focus on several ATLAS searches for new physics involving third generation particles, both targeting extended Higgs sectors and vector-like quarks.

Tuesday November 15 2016 at 1:30pm in 4C8
Matthew Klein, Columbia University
Search for supersymmetry in events with four or more leptons at ATLAS

Tuesday November 1 2016 at 1:30pm in 4C8
John Alison, University of Chicago
Di-Higgs at the LHC: Current Status and Future Prospects
I will discuss motivations for searching for di-Higgs production at the LHC. Recent results and projected sensitivities will be presented with particular emphasis on the dominant hh->4b channel.

Thursday October 27 2016 at 3pm in room DRL A6
Andrew Missert, University of Colorado, Boulder
Improving T2K Oscillation Results with a Maximum Likelihood Event Reconstruction
The Tokai-to-Kamioka (T2K) experiment is an accelerator-based long-baseline neutrino oscillation experiment that uses a unique off-axis neutrino beam to precisely measure the parameters that govern neutrino flavor oscillations. This talk will outline the experiment and the current results, which offer tantalizing hints regarding the existence of CP violation in the neutrino sector. It will also cover future improvements to the T2K analysis, most notably the development of a new maximum-likelihood event reconstruction algorithm for Super Kamiokande, which could be used to squeeze even more information about the oscillation parameters from the existing data.

Friday October 14 2016 at 1:30 pm in room 4C6
Precision Timing Detectors for Particle Physics
High energy particle collider experiments are facing ever more challenging conditions, operating at todays accelerators which are providing instantaneous luminosity of 1034 cm-2s-1 and above. The high center of mass energy, the large number of simultaneous collisions of beam particles and the very high repetition rates of the collision events pose huge challenges. This results in extremely high particle fluxes, causing very high occupancy in the detectors operating at these machines. Detectors which can provide timing measurements with a precision of a few 10 ps and below can be a major aid in the reconstruction of the physics events under such challenging conditions. In this talk I will present a broad range of R&D activities on precision timing detectors with a focus on calorimeter based measurements. I will discuss possible implementations of precision timing detectors for the upgrades of the LHC detectors to cope with the conditions expected at the high luminosity upgrade of the accelerator as well as for future colliders.

Colloquium: Primakoff lecture, October 13
Rolf Heuer, CERN (former director general)

Tuesday September 20 2016 at 3pm in room 2C8
Jonathan Insler, Drexel University
Results from the DUNE 35-ton Prototype Detector
The 35 ton prototype for the Deep Underground Neutrino Experiment (DUNE) far detector was a single phase liquid argon time projection chamber (LAr-TPC) integrated detector that took cosmics data for a six week run from February to the middle of March 2016. The 35 ton was built to test the liquid argon technologies to be used by the full size DUNE far detector in a fully integrated system. The 35 ton had two drift volumes of lengths 2.23 m and 0.23 m on either side of its anode plane assembly (APA) and made use of wire planes with wrapped wires and a photon detection system (PDS) utilizing photon detection panels read out by silicon photomultipliers (SiPMs). We present an analysis of 35 ton detector cosmics data with a focus on the performance of the PDS.

Tuesday May 24 1:30pm in 3c4
Alexis Popkow, UCLA
Galactic Very High Energy Astrophysics
Despite being discovered over a hundred years ago, the origin of cosmic rays has remained a mystery. Recent clues suggest that a large number are accelerated in supernova remnants in our Galaxy. The Cygnus region is a very active region of our Galaxy, with many sources of GeV and TeV gamma-ray emission, such as supernova remnants, pulsar wind nebulae, and massive star clusters. A detailed study of the Cygnus region can give insight into the processes of particle acceleration in astrophysical sources, and the nature of cosmic rays. VERITAS (Very Energetic Radiation Imaging Telescope Array System) is an array of four 12 meter diameter imaging atmospheric Cherenkov telescopes located at Mt Hopkins, AZ, USA. From 2007 through 2012 it gathered nearly 300 hours of data in the Cygnus region from 67 to 82 degrees Galactic longitude and from -1 to 4 degrees in Galactic latitude. We are reanalyzing the VERITAS data with updated analysis techniques, and will be cross correlating that data with the results of an analysis of over five years of Fermi-LAT data in the region. Using a cross correlation of these results we can motivate continued observations in this active region of the Galaxy.

Monday May 16 3:30pm in **3N6**
Jordan Myslik, University of Victoria
Muon antineutrino oscillations at T2K
The T2K ("Tokai to Kamioka") experiment is a long-baseline neutrino oscillation experiment in Japan. A beam of muon neutrinos or muon antineutrinos is produced at the Japan Proton Accelerator Research Complex (J-PARC) in Tokai. The unoscillated neutrino flux is measured by the near detector complex 280 m from the proton target, and the oscillated neutrino flux is measured by the far detector, Super-Kamiokande, 295 km away. Using a beam of muon neutrinos, T2K has performed precise measurements of muon neutrino disappearance, and discovered muon neutrino to electron neutrino oscillation by measuring electron neutrino appearance. Since the summer of 2014, T2K has been taking data using a beam of muon antineutrinos, and has released the results of both a muon antineutrino disappearance analysis and an electron antineutrino appearance analysis, both using antineutrino beam data up to the summer of 2015. This talk will discuss these analyses, going into detail about the role played by the near detector, and looking at future directions.

Wednesday May 4 1:00pm note time in 4N12 note place
David Nygren, University of Texas Arlington
Searches for Neutrino-less Double Beta-Decay: a Decade of Discovery Ahead at the ton-scale?
Observation of neutrino-less double beta-decay would demonstrate that the neutrino and anti-neutrino are identical. This decay mode would be prohibited if the neutrino has zero mass but the discovery of neutrino oscillations, demonstrating a non-zero mass, has strongly motivated new experimental searches. While knowledge of mass and phases is incomplete, oscillation results have provided a target range of desired search sensitivity, about a factor of about 100 greater than the current experimental limits. I will present a personal perspective on current experimental aspirations in the international context. A 'discovery class' experiment requires a ton-scale active mass and background levels reduced by more than two orders of magnitude. Is this technically possible? For the US, an opportunity appears to exist in the use of gas-phase xenon with development of new methods for background reduction, as pursued within the NEXT collaboration. The elusive neutrino may yet provide more surprises, even insight as to why there is something, rather than nothing.

Thursday April 28 11:00am in 3W2
Keisuke Yoshihara, Penn
Recent results on SUSY searches in LHC-ATLAS
Despite the absence of experimental evidence, weak scale supersymmetry (SUSY) remains one of the best motivated and studied SM extensions as a solution for hierarchy problem. This talk summarizes the recent ATLAS results on SUSY searches using ~3/fb of 13TeV proton-proton collisions in 2015 and discusses what to do next in the coming years.

Tuesday April 5 1:30pm in 3W2
Chris Hays, Oxford University
Effective field theory and the LHC: New physics through precision measurement

Tuesday March 29 1:30pm in 3W2
Jeff Dandoy, University of Chicago
Search for new phenomena in the dijet channel with the ATLAS detector at 13 TeV
With the beginning of Run II at the LHC, proton-proton collisions at a center of mass energy of 13 TeV have introduced new potential for observing physics beyond the Standard Model. The increase in center of mass energy greatly enhances the reach of searches for any new exotic particles, particularly with decay modes involving a dijet system. With 3.6 fb^{-1} collected so far in Run II, the sensitivity to new resonant particles has already surpassed the limits set with the full Run I dataset. The ability to observe non-resonant deviations from the SM such as structure within quarks themselves has also been greatly enhanced from the new operating conditions of the LHC. I will present the first results of searches for both resonant and non-resonant new physics in dijet events.

Tuesday March 22 1:30pm in 3W2
Joe Taenzer, University of Toronto
Studying V(H → WW*) with the ATLAS detector and Global sequential corrections for ATLAS jets

Tuesday March 15 1:30pm in 3W2
Philip Chang, University of Illinois
Searches for new physics in the Higgs sector
The discovery of the Higgs boson opened up a new frontier for new physics searches. One example is the study of the Higgs couplings. Precise measurement of the Higgs couplings can put constraints on new physics. I will discuss the couplings measurement in H->WW decay channel that provides the best single channel measurement. I will also then briefly discuss other ways of searching for new physics in the Higgs sector for the future.

Tuesday March 1 2016 in 3W2 at 1:30pm
Sadia Khalil, Kansas State University
Searches for Vector-like quarks at CMS experiment, at the LHC.
I will present results of searches for massive top and bottom quark partners using proton-proton collision data collected with the CMS detector at the CERN LHC at a center-of-mass energy of 8 TeV. These fourth-generation vector-like quarks are postulated to solve the Hierarchy problem and stabilize the Higgs mass, while escaping constraints on the Higgs cross section measurement. The vector-like quark decays result in a variety of final states, containing top and bottom quarks, gauge and Higgs bosons. I will present searches using several categories of reconstructed objects, from multi-leptonic to fully hadronic final states. At 8 TeV, we set exclusion limits on both the vector-like quark mass and pair-production cross sections, for combinations of the vector-like quark branching ratios. I will also present these searches using 13 TeV collision data.

Tuesday February 23 2016 in 3W2 at 1:30pm
David Shih, Rutgers University
Natural Supersymmetry Today
I'll give a broad overview and survey of my work and others on the challenges confronting naturalness and supersymmetry after Run I of the LHC.

Colloquium: Wednesday February 17 4:15pm in A8
Lian Tao Wang, University of Chicago
Physics opportunities at future circular colliders

Tuesday February 9 2016 in 3W2 at 1:30pm
Russell Neilson, Drexel University
PICO: Searching for Dark Matter with Bubble Chambers
The PICO collaboration uses bubble chambers to search for WIMP dark matter particles. The bubble chambers are operated in a moderately superheated state providing superb rejection of the dominant gamma background at better than the 10^-10 level, and are filled with fluorinated target fluids ideally suited for investigating spin-dependent WIMP-proton interactions. PICO is currently running two experiments at the deep underground SNOLAB site: PICO-60 (previously called COUPP-60) and PICO-2L. I will present results from recent dark matter searches in both of those experiments. I will also discuss studies of unexpected backgrounds that have impacted those dark matter searches and future plans for the two experiments.

### Seminars in 2015

Tuesday December 1 2015 in 3W2 at 1:30pm
Yangyang Cheng, University of Chicago
Tracking to the Dark Side at ATLAS: the Present and the Potential

Tuesday November 17 2015 in 3W2 at 1:30pm
Michelle Dolinski, Drexel University
Searching for neutrinoless double beta decay with cryogenic xenon detectors

Thursday November 12 2015 in 3W2 at 1:30pm
Sinead Farrington, Warwick University
Results on the Standard-Model-like Higgs boson at LHC Run 1

Tuesday September 22 2015 in 3W2 at 1:30pm
Nick Ryder, University of Oxford
The SoLid Experiment: searching for neutrino oscillations within 10 m of a nuclear reactor

Tuesday June 2 2015 in 3W2 at 1:30pm
Kristin Lohwasser, DESY-Zeuthen
The WW puzzle: Measurement of diboson production at the LHC
The measurements of the production of W boson pairs in pp collisions at 7 and 8 TeV have shown a small but consistent excess of 1-2- sigma over the theoretical predictions, causing a bit of a stir amongst theorists and experimentalists alike. The recent results from the updated ATLAS measurements for the total and fiducial cross sections are presented together with a study of differential distributions as well as limits on anomalous triple gauge couplings.

Thursday April 30 2015 in 2C4 at 1:30pm
Mike Hance, LBNL
Searching for Exotic Heavy Leptons and Diboson Resonances at the LHC

Tuesday April 28 2015 in 3W2 at 1:30pm
John Paul Chou, Rutgers
Recent CMS Searches from Run 1 and Prospects for Run 2

Thursday April 23 2015 in 2C4 at 1:30pm
Andrew Brinkerhoff, Notre Dame
A new measurement of ttW and ttZ at CMS
For the first time at the LHC, we are able to measure the associated production of W or Z bosons with top quark pairs. These processes allow us to directly measure the top-Z coupling, and place limits on effective couplings between the top quark and the Higgs, W, and Z bosons. In addition, ttW and ttZ are important backgrounds in searches for ttH and new physics processes in the top sector, especially SUSY models. I will present recent results from ATLAS and CMS, and describe a new technique to reconstruct the ttW and ttZ systems, allowing for more precise measurements with existing data.

Tuesday April 21 2015 in 3W2 at 1:30pm
Justin Khoury, Penn
Dark matter superfluidity

Thursday April 16 2015 in 2C4 at 1:30pm
Ben Carlson, University of Pittsburgh
Search for stealth supersymmetry at the LHC
slides
Supersymmetry (SUSY) can simultaneously solve the hierarchy problem, allow unification of the fundamental interactions, and provide a candidate for dark matter. Most searches for SUSY focus on the presence of large missing transverse energy (MET) carried away by the lightest SUSY particle. Recent high-MET searches at the CERN LHC have not yet found evidence for SUSY. Therefore, it is important to study well-motivated alternatives with low-MET, such as models characterized by R-parity violation, compressed spectra, and hidden valleys. In particular, the "stealth SUSY" model yields a low-MET signature while conserving R-parity by means of a new hidden sector in which SUSY is approximately conserved. I will present recent LHC searches for stealth SUSY, and discuss interesting areas for study at 13 TeV.

Tuesday April 14 2015 in 3W2 at 1:30pm
Brian Hamilton, University of Maryland
New results from LHCb
I will present several new results based on the full dataset collected by the LHCb detector during the 2011 and 2012 running periods. In particular, the first measurement from LHCb of the magnitude of the CKM matrix element Vub via semileptonic decays of the $\Lambda_{b}$ baryon and its impact on contributions of right handed currents will be discussed. I will also present new results on the electroweak penguin decay $B \to K^{*} \mu\mu$ and the status of anomalies in this channel observed in the previous analysis which used a subset of the full data. Plans for the LHCb experiment during Run 2 of the LHC and beyond will also be discussed.

Thursday April 2 2015 in 2C4 at 1:30pm
Alex Tuna, University of Pennsylvania
Higgs boson decay to tau+ tau-

Tuesday March 31 2015 in 3W2 at 1:30pm
Ben Hooberman, University of Illinois
Recent results from LHC dilepton+jets+missing transverse momentum Searches
The discovery of a Higgs boson at the LHC has answered critical open questions in the standard model. Despite strong evidence that the standard model is incomplete, no compelling evidence for beyond-the-standard model physics has been observed. However, two recent searches from CMS and ATLAS in the dilepton + jets + ETmiss final state have uncovered moderate excesses with respect to standard model predictions, at the level of ~2.5-3.0sigma. This talk will discuss the strategy, background estimation, and results of these searches, as well as possible signal interpretations in supersymmetric models.

Thursday March 26 2015 in 2C4 at 1:30pm
John Alison, University of Chicago
Fast Track Finding at the LHC

Tuesday March 24 2015 in 3W2 at 1:30pm
Chase Shimmin, University of California at Irvine
Observing Ultra-High Energy Cosmic Rays with Smartphones
In this talk I discuss the possibility of using a network smartphones and similar devices to search for ultra-high energy ($>10^{18}$ eV) cosmic rays via a community-sourced scientific platform. Muons and energetic photons produced in UHECR events leave a signature of bright pixels in images from on-board CMOS cameras, while GPS location data allows for the reconstruction of extensive air showers observed by multiple devices. The ubiquity of these consumer devices around the globe enables instrumenting a far greater area than conventional observatories, enhancing sensitivity to the very rarest events. Given certain levels of participation, it is even possible to match the observational power of state-of-the-art facilities such as the Pierre Auger observatory, at the highest energies.

Tuesday March 17 2015 in 3W2 at 1:30pm
John Campbell, Fermi National Accelerator Lab
Monte Carlo for FeMtobarn processes (MCFM) and related topics

Wednesday March 4 2015 at 2:00pm in 2C4 at 2:00pm
Alberto Belloni, University of Maryland
Looking towards 2025 - Preparing the CMS hadronic calorimeter for the High-Luminosity LHC runs

Tuesday Mar 3 2015 at 1:30pm in Room 3W2
Reserved for search

Tuesday Feb 24 2015 at 1:30pm in Room 3W2
Holger Muller, University of California, Berkeley
Atom interferometry measurements in fundamental physics
Chameleons are flexible models for dark energy that avoid conflict with laboratory experiments by becoming short-ranged in the presence of dense objects. Probing the chameleon field with atoms rather than bulk matter strongly reduces this "screening." We developed an atom interferometer inside an optical cavity [1] to reach high reproducibility in tight spaces. Our experiment is the first to rule out a range of chameleon and other dark energy candidates that would reproduce the observed cosmic acceleration [2].
We will also comment on our measurement of the fine structure constant, for which we have boosted atom interferometry into the 10^-10 range by suppressing the effects of so-called diffraction phases [3]. After six data taking campaigns we are close to reporting a new measurement with an anticipated accuracy of about 0.25 parts per billion. This would be similar to the one of the electron's gyromagnetic anomaly g-2, allowing for new precise tests of quantum electrodynamics.
[1] arxiv:1409.7130. Phys. Rev. Lett., in press.
[2] arXiv:1502.03888.
[3] arXiv:1410.8486.

Tuesday Feb 17 2015 Room 3W2
Reserved for search

Thursday Feb 12 2015 Room 2C4
Reserved for search

Tuesday Feb 10 2015 Room 3W2
Reserved for search

Thursday Jan 29 2015 Room 2C4
Reserved for search

Tuesday Jan 20 2015 Room 3W2
Reserved for search

### Seminars in 2014

January 14
Nuno de Barros, Technical University, Dresden
First results on neutrinoless double beta decay from the GERDA experiment
The GERmanium Detector Array (GERDA) is an experiment designed to search for neutrinoless double beta decay in 76-Ge, with bare germanium detectors being operated in a cryostat with 65 cubic meters of liquid argon. This lepton number violating process is predicted by models beyond the Standard Model of particle physics and its successful observation would imply that neutrinos are Majorana particles. Provided that the exchange of light Majorana neutrinos is the leading mechanism of neutrino-less double beta decay, measuring or constraining the half-life sheds also light on the absolute neutrino mass scale. The experiment started its first phase of operation in November 2011 and ended in May 2013, when an exposure of 21.6 kg.yr was achieved. Taking under consideration the background index, this exposure allows to test the existing claim of neutrinoless double beta decay observation by a subset of the Heidelberg-Moscow collaboration. In this talk the GERDA experiment will be introduced and the results of the first phase of the experiment will be presented. Furthermore, the status of the preparations for the second phase of the experiment will also be shown, which will have twice as much active mass and a goal background index of 1 x 10^-3 cts / (keV kg yr), one order of magnitude lower than the goal of phase I.

January 21
Tae Min Hong, Penn
Practice talk for Fermilab Wine & Cheese

January 28
Chris Meyer, University of Chicago
Dijet production at ATLAS and an improved method for theory comparison
Following the successful completion of Run-I at the LHC, a large number of precision Standard Model measurements are being published. I will focus on the recent dijet production paper, which uses the full 2011 data sample (4.5/fb). In particular, this result uses an improved statistical method for quantitatively comparing theoretical predictions with the data. This method will be a strong tool for determining which PDF sets best describe data in future analyses. Finally, a model of contact interactions is used to show that the published cross sections and their uncertainties can be used by the general community to constrain new models of physics.

February 18
Michael Mooney
Search for the SM Higgs Boson Produced in Association with a Vector Boson and Decaying to Bottom Quarks at the CMS Detector
A search for the Higgs boson produced in association with a W or Z boson and decaying to bottom quarks is presented. A sample of approximately 24/fb of data recorded by the CMS experiment at the Large Hadron Collider, operating at center-of-mass energies of 7 TeV and 8 TeV in 2011 and 2012, respectively, is used to search for events consistent with the signature of two b-jets recoiling with high momentum from a W(lnu), Z(ll), or Z(nunu) decay, where l = electron or muon (or hadronically-decaying tau particle in the case of W bosons). Observed signal significance and 95% confidence level upper limits on the production cross-section relative to the Standard Model prediction are presented for the 110-150 GeV Higgs mass range.

September 16 2014
Joana Miguens, LIP,Portugal
Higgs boson measurements in the H->WW*->lvlv channel with ATLAS
(slides)
After the discovery at the LHC, precision measurements of the Higgs boson are essential to determine its nature. The H->WW*->lvlv decay channel offers a sensitive experimental signature. The Higgs resonance mass cannot be reconstructed because of the two neutrinos in the final state. Nonetheless, once the backgrounds are under control, the large H->WW* branching fraction and good signal-to-background ratio provide powerful measurements of the Higgs production and couplings. I will present the analysis and discuss the results from ATLAS on the H->WW*->lvlv channel, based on the full dataset collected during Run-I of the LHC, where an excess of events is observed, providing evidence for the Higgs boson at mH=125GeV.

September 30 2014
Chunhui Chen, Iowa State University
Production of high transverse momentum vector bosons reconstructed as single jets and its application to search for NP at the LHC (slides)
Highly boosted hadronically decaying particles have been widely used as a unique signature to search for NP at the LHC. In this talk, we present a measurement of the cross-section for high transverse momentum W and Z bosons produced in *pp* collisions and decaying to all-hadronic final states by ATLAS experiment. The measurement is performed by reconstructing boosted W or Z bosons in single jets. The reconstructed jet mass is used to identify the W and Z bosons, and a jet substructure method based on energy cluster information in the jet center-of-mass frame is used to suppress the large multi-jet background. In this talk, we will also discuss potential applications of the jet substructure in the jet rest frame in searches for NP at the LHC.

October 28 2014
Naoko Kurahashi Neilson, Drexel
Detecting Cosmic Neutrinos with IceCube at the Earth's South Pole
The IceCube Neutrino Observatory has recently discovered a diffuse flux of astrophysical neutrinos, neutrinos from beyond the solar system. But how does one collect neutrinos at the South Pole? Why study neutrinos for astronomy? In this talk, I will try to answer such questions and show nice pictures from Antarctica. I will also discuss the multiple diffuse flux analyses in IceCube that observe the astrophysical flux, and what each can tell us. Spatial analyses that aim to identify the sources of such astrophysical neutrinos will also be discussed, followed by an attempt to reconcile all results, to draw a coherent picture that is the state of neutrino astronomy.

### Seminars in 2013

November 12
Keisuke Yoshihara, University of Tokyo
Evidence for the Higgs Boson in the H to WW* to llnunu Channel from the ATLAS Experiment at the LHC
Evidence for the Higgs boson in the H to WW* to ll nunu Channel is presented using the complete 2011 and 2012 data samples collected with the ATLAS detector at the LHC. The analysis focuses on a mass of mH = 125 GeV, where an excess over the expected number of background events is observed. A preliminary result of coupling and rate measurement is presented along with some details on the object selection and background estimation.

November 19
Karen Gibson, Case Western
First Dark Matter Search Results from the LUX Detector
I will present the results from 85 days of data collected by the LUX experiment. The LUX detector is a two-phase xenon time-projection chamber designed to search for the scattering of WIMP dark matter in liquid xenon. LUX has been operating underground at the 4850' level of the Sanford Underground Research Facility in Lead, SD, since February 2013, and WIMP search data was collected between April and August 2013. I will review the unblinded analysis of our initial dataset and discuss the results from our search, which provides world-leading sensitivity to WIMP dark matter.

November 26
Sogee Spinner, University of Pennsylvania
Linking Neutrino and Collider Physics through a Theory of R-parity Violation
Proton decay bounds have forced the ad hoc R-parity discrete symmetry to be an integral part of the minimal supersymmetric standard model thereby associating supersymmetry with missing energy signals at the Large Hadron Collider. I will discuss an alternative picture, the minimal version of which to leads to spontaneous R-parity violation with a stable proton. It is further well motivated by string theory. Neutrino masses are generated through R-parity violation therefore intimately connecting the neutrino sector to the decay of the lightest supersymmetric particle (LSP), which is no longer stable. This will be discussed within the context of a stop LSP. Other interesting predictions of the model will be highlighted.

December 3
Nathaniel Craig, Rutgers University
New Searches involving the Higgs boson.
The discovery of a Higgs-like particle at the LHC provides an unprecedented opportunity for the pursuit of physics beyond the Standard Model. In this talk I'll propose various strategies to look for new physics via the Higgs -- including measurements of Higgs couplings and associated indirect observables; searches for Higgs production in association with new physics; and prospects for probing extended electroweak symmetry breaking sectors.

December 10
Patrick Meade, Stony Brook University
Finding new physics in unexpected places
I’ll describe examples of well motivated BSM physics that may be in current LHC data which is not excluded by direct searches. I’ll discuss the implications of this for data driven background methods, and possible new search strategies for the second run of the LHC

### Seminars in 2012

Tuesday January 17 at 1:30pm
Drexel University
Results from Double Chooz

Tuesday April 17 at 1:30pm
Geralyn Zeller
Fermilab
Unanswered questions in neutrino scattering

### Seminars in 2011

Tuesday January 18 at 1:30pm
Rick Van Berg
PENN
LSST (pdf slides)

Tuesday January 25 at 1:30pm
Corrinne Mills
Harvard
W physics results at ATLAS (pdf slides)
The 2010 LHC data from proton-proton collisons at sqrt(s) = 7 TeV give us our first look at matter and forces at an energy scale unprecedented at colliders. W bosons decaying to a charged lepton and a neutrino are a benchmark Standard Model process, and has the highest cross section of any process producing isolated high-momentum leptons. Although the integrated luminosity of this first data is orders of magnitude below what is projected for the next few years of LHC running, there is already a sufficient number of W candidates to begin characterizing W production at the LHC. I will show measurements by the ATLAS collaboration of the inclusive W cross section and lepton charge asymmetry, and describe a measurement in progress of the transverse momentum distribution of the W. These and similar measurements test our understanding of a new detector and of physics at a new energy scale, establishing the foundation needed to search for evidence of new particles and phenomena.

Tuesday February 1 at 1:30pm
Amit Lath
Rutgers
Search for a new hadronic resonance using jet ensembles at CDF (pdf slides)

Tuesday February 15 at 1:30pm
Mariangela Lisanti
Princeton
Model-Independent Searches at the LHC
EVO Video Recording
Tuesday February 22 at 1:30pm
Doug Glenzinski
Fermilab
The Mu2e experiment
EVO Video Recording

Tuesday March 1 at 1:30pm
Stan Seibert
University of Pennsylvania
MiniCLEAN
EVO Video Recording
Tuesday March 15 at 1:30pm
Daniel Whiteson
University of California, Irvine
Exploring the unknown universe with the LHC
EVO Video Recording
Collisions at the Large Hadron Collider (LHC) let us explore a new territory nearly four times larger than anything previously examined. This energy frontier may be populated with new particles which (1) shed light on the nature of dark matter (2) extend the current table of the fundamental particles (3) demonstrate the existence of new fundamental forces or (4) reveal startling and completely unexpected properties. I will describe a strategy for searching this territory, show the state of the art from the Fermilab Tevatron collider and present first results from the ATLAS detector at the LHC.

Tuesday March 22 at 1:30pm
Richard Hughes
Ohio State University
Recent CDF results on the Standard Model Higgs Search
EVO Video Recording

Tuesday March 29 at 1:30pm
Roy Briere
Carnegie Mellon University
Early results and prospects at BESIII
EVO Video Recording

Tuesday April 5 at 1:30pm
Sarah Demers
Yale University
Recent results from ATLAS on W -> tau nu
EVO Video Recording

Tuesday April 12 at 1:30pm
Kathy Copic
Columbia University
Recent results from ATLAS on W' and Z' searches
EVO Video Recording

Tuesday April 19 at 1:30pm
Richard Gray
Rutgers University
Recent results from CMS on multilepton searches
EVO Video Recording

Thursday April 21 at !Note time! 3:00pm
Peter Wittich
Cornell University
Recent results from CMS on W' searches
EVO Video Recording

Tuesday April 26 at 1:30pm
Brian Winer
Ohio State University
Recent results from FERMI
EVO Video Recording

Wednesday October 19 at 1:30pm in 3W2
Dima Kovalskyi
UCSB
Recent search results for H->WW with CMS

Tuesday November 1 at 1:30pm
Jeff Temple
University of Maryland
Recent search results for stopped gluinos with CMS

Tuesday November 8 at 1:30pm
Alex Wright
Princeton University
Recent results from Borexino

### Seminars in 2010

Tuesday January 19 at 1:30pm
Sean Grullon
University of Wisconsin
Searching for High Energy Diffuse Astrophysical Muon Neutrinos with IceCube (slides pdf)

The IceCube Neutrino Observatory is a 1 km^3 detector currently under construction at the South Pole. Searching for high energy neutrinos from unresolved astrophysical sources is one of the main analysis strategies used in the search for astrophysical neutrinos with the IceCube Neutrino Observatory. A hard energy spectrum of neutrinos from isotropically distributed astrophysical sources could contribute to form a detectable signal above the atmospheric neutrino background. A reliable method of estimating the energy of the neutrino-induced lepton is crucial for identifying astrophysical neutrinos. An analysis is underway using data from the 40 string configuration taken during its 2008-2009 science run.

Tuesday February 9 at 1:30pm
Hugh Lippincott
Yale University
DEAP/CLEAN: Detecting dark matter with liquid argon (and neon)

The DEAP/CLEAN collaboration has proposed to use liquid argon and neon as targets for dark matter and solar neutrinos. I will discuss measurements of scintillation of these liquids performed at Yale, in particular focusing on the use of pulse shape discrimination to reject electronic recoil backgrounds in liquid argon. I will also discuss studies of alpha and nuclear recoil backgrounds in a prototype detector currently operating at the underground facility at SNOLAB. If time permits, I will mention simulations of a large neon detector and their implications for detecting /pp/ solar neutrinos.

Wednesday March 3 at 2:00pm
Aubra Anthony
Joint Seminar with Astrophysics-Cosmology
Studying the Sun with SNO: Searching for high-frequency variations in the solar neutrino flux (slides pdf)

Recent helioseismology results have pointed to the possible detection of high-frequency (periods of minutes to days) gravity-mode oscillation signals in the Sun. Periodic fluctuations in density, pressure and temperature (as would be caused by g-modes at the solar core) could potentially modulate the outgoing flux of solar neutrinos, through the close relationship between temperature and neutrino production. Density fluctuations could also affect the propagation of neutrinos through the sun, through the MSW effect, because periodically-shifting matter densities could temporally vary the probability for neutrino oscillations to occur. The Sudbury Neutrino Observatory was an optimal laboratory for studying time dependence in the solar neutrino flux, due to excellent background elimination and real-time signal detection. I will discuss the searches that we performed with SNO neutrino data to identify any high-frequency periodic signal in the sun, both on broad time scales, as well as those specifically relevant to recent g-mode detection claims.

Tuesday March 23 at 12:00pm in 2C6
Frank Tackmann
MIT
Event shapes for jet measurements at the LHC

I discuss a new class of event shapes for hadron colliders which are inclusive observables whose purpose is to enforce a certain number of (central) jets in the final state. The simplest case is beam thrust in Drell-Yan, pp -> X l+l-. Requiring tau_B << 1 provides an inclusive veto for central jets while allowing forward radiation. Beam thrust is one of the simplest hadronic observables measurable at a hadron collider and can provide crucial tests of our understanding of initial state radiation. I comment on the theoretical calculation of the cross section at small tau_B and present explicit results at NNLL, which represents the first NNLL resummation for a hadron collider event shape. I also discuss the generalization of beam thrust to processes with one or more jets. For a certain desired number of jets, the generalized event shape allows one to constrain additional radiation in the event and veto undesired jets.

Wednesday April 7 at 4:00pm
Sheldon Stone
Syracuse University
The LHCb Experiment (slides pdf)

I will discuss the physics objectives, design, commissioning, and first data from the LHCb experiment. I will also present our plans for an Upgrade.

Monday May 10 at 1:00pm
Ilija Bizjak
University College London
The W-Mass measurement at CDF (slides pdf)

## Info for Watching Video recordings

Download the zip file and uncompress the video folder. In the folder should be a number of files one of which will have EVO file extension. Next go to EVO's website at http://evo.caltech.edu/ and click on the "Recording Player" (Please note that Java needs to be installed to launch this application). Once the recording player has launched go to "File" and then "Open" and navigate to where the uncompressed folder/files are on your computer. Click on the file with the .EVO file extension in the video folder and click the "Open" button. This should launch the video recording windows and the video will start playing. For more information on EVO please refer EVO's website.

Tuesday October 26 at 1:30pm
Paul Langacker
IAS Princeton
Z' physics (slides pdf)

Tuesday November 16 at 1:30pm
Burt Ovrut
Penn
B-L MSSM (slides pdf)

Tuesday December 7 at 1:30pm
Sogee Spinner
Wisconsin
The Fate of R-parity(slides pdf)
One of the outstanding problems of supersymmetry is an understanding of the baryon and lepton number violating terms allowed in the minimal supersymmetric standard model (so-called R-Parity violating terms). Explanations which are linked to TeV scale physics are exciting due to their testability in the near future. I will discuss some TeV scale models, which provide a framework for understanding R-parity by utilizing it's connection to baryon minus lepton number symmetry(B-L). I will also outline some possible collider implications of such models.
Tuesday December 14 at 1:30pm
Tricia Vahle
William & Mary
New results from MINOS (slides pdf)
MINOS records interactions of neutrinos produced by the Fermilab NuMI beam line in two detectors, 734 km apart. Comparisons of the energy spectra and beam composition at the two sites yield precision measurements of neutrino oscillations for L/E $\sim$ 500 km/GeV. In this paper, updated results from an integrated exposure more than twice that of earlier publications will be presented. We will present a measurement of the probability of muon-neutrino disappearance as a function of energy and of the neutrino oscillation parameters \dmsq{32} and \sinsq{23}. We will report on the measurement of neutral current interaction rates in each detector, which enables a search for light neutrino families that do not couple via the weak interaction. We will also discuss results from the search for electron-neutrino events in the Far Detector, which probes the value of the mixing angle $\theta_{13}$. Finally, we will discuss a dedicated antineutrino run, which allows for measurement of antineutrino oscillation parameters.

### Seminars in 2009

Tuesday January 20 1:30pm
Richard Van de Water
Los Alamos National Laboratory
Anti-Neutrino Oscillation Results from MiniBooNE (slides pdf)
The first MiniBooNE neutrino oscillation results published April of 2007 ruled out the simple two neutrino oscillation hypothesis of the LSND experiment. However, MiniBooNE unexpectedly observes a significant excess of electron-like events below a reconstructed neutrino energy of 475 MeV. For the last two years MinibooNE has been running in anti-neutrino mode. The anti-electron neutrino data sample can shed light on the neutrino low energy excess since they share many of the same backgrounds and systematic errors. As well, a search for oscillation at higher energy can be performed. Updated results of the neutrino low energy excess and new anti-neutrino oscillation results will be presented.
Tuesday February 3 1:30pm
Melissa Jerkins
University of Texas at Austin
Neutrino physics using cold atoms (slides pdf)
Recent advances in atomic slowing and cooling are opening new avenues through which to explore neutrino properties. I will discuss several potential applications of these technologies to neutrino research, including new concepts for tritium beta-decay and neutrino Mossbauer experiments. The absolute mass scale of the neutrino has long been probed through tritium beta-decay, but these technically challenging experiments have so far been unable to detect the neutrino mass. By utilizing a slow, cold beam of tritium atoms to create the tritium source, one could detect both the helium ion and the beta, which implies that the neutrino mass could be directly reconstructed. I will present simulation results and discuss the feasibility of both a three-body tritium beta-decay experiment and a boundstate tritium beta-decay experiment. I will also discuss preliminary explorations of a neutrino Mossbauer experiment in which advances in magnetic slowing of atoms allow trace detection of tritium created in recoilless reverse tritium beta decay. Observation of the Mossbauer effect with neutrinos would be an exciting first step toward tabletop neutrino oscillation experiments.
Tuesday February 10 1:30pm
Francesco Polci
LAL Orsay
Searching for the Higgs boson with ATLAS (slides pdf)
The beginning of the operations of the Large Hadron Collider is a crucial event for particle physics. The LHC will allow to explore a very large mass region where we expect to find the Higgs boson, a fundamental brick in particle physics theories. Waiting for collisions, ATLAS prepares the searches for the Higgs boson both in the Standard Model and in the supersymmetric theoretical frameworks. The different channels studied, the analysis techniques and the most recent estimations of the discovery potential will be presented, with a particular focus on the analysis of the disintegration of the Higgs into a pair of photons.
Tuesday March 17 1:30pm
Bryan Fulsom
University of British Columbia
Radiative Decays of the X(3872) in BaBar
The X(3872) was the first of many puzzling new heavy quarkonia states to be discovered in the B Factories. Yet after six years of study, the questions regarding its internal structure remain unsolved. Is it a conventional charmonium state, or does it represent something more exotic, such as a four-quark molecule? In this talk, I will review the experimental evidence for the X(3872) and discuss how radiative decays to ccbar gamma could prove important in solving this mystery. I will present the results of the search for decays of the X(3872) to J/psi gamma and psi(2S) gamma using the full BaBar dataset, and discuss their impact on our understanding of the X(3872).
Tuesday March 24 1:30pm
Professor Gabriella Sciolla on behalf of the DM-TPC collaboration
MIT
DM-TPC: a novel apparatus for directional Dark Matter detection (slides pdf)
Directional detection is key to provide unambiguous observation of dark matter even in the presence of insidious backgrounds. The DM-TPC collaboration is developing a TPC with optical readout with the goal of detecting the sense and direction of the elastic recoils generated by Dark Matter interactions. The detector, filled with CF_4 gas at low pressure, is equipped with a mesh-based amplification region that allows for 2D imaging of the recoils in a CCD camera. The third coordinate of the recoil is provided by PMTs. The sense of the direction is determined by measuring the energy loss along the recoil track. The performance of this detector has been studied using alpha particles, low-energy neutrons, and x-rays. Results from a first prototype clearly demonstrated the suitability of this approach to measure directionality by observing the "head-tail" effect for low- energy nuclear recoils. Two 10-liter prototypes of the DMTPC detector have recently been built, and are ready to be moved to an underground laboratory for a one-year run in 2009. A larger (1m^3) detector is also being designed. A one-year underground run with such detector will allow us to improve the current sensitivity on spin-dependent interaction on protons by about a factor 50.
Tuesday May 1 1:30pm
Andrew Brandt
University of Texas, Arlington
Forward Protons from the SPS to the LHC
This seminar gives an overview of diffractive physics at hadron colliders, focusing on proton detectors from the early days of hard diffraction at the SPS to the new joint ATLAS/CMS FP420 project designed to use diffraction as a tool to measure properties of the Higgs Boson.
Wednesday May 6 1:00pm
Robert Knapik
The Cosmic Ray Energy Spectrum Measured by the Pierre Auger Observatory
The origins of comic rays with energies greater than 1018 eV are very uncertain. This talk highlights comic ray detection with emphasis given on how the energy of an event is determined, specifically, on how the atmosphere is used as a calorimeter. The Pierre Auger Observatory was able to take data during construction but was only fully completed last summer. Already Auger has accumulated more data than all previous experiments combined. The energy spectrum measured by Auger is compared with previous experiments and the systematic differences that exist between measured spectra are discussed. The energy spectrum, along with arrival direction studies and primary particle identification, are used to constrain models for the sources of high energy cosmic rays. The astrophysical implications of the early Auger results and the next steps for the Observatory are presented.
Tuesday September 1
Tae Min Hong
University of California, Santa Barbara
Looking for patterns in B-meson decays with baryons at BaBar

Tuesday September 22 at 1:40pm
Tom Schwarz
University of California, Davis
Top Quark Production at the Tevatron (slides pdf)
The Tevatron has now produced over 10 times the statistics since the discovery of the Top quark over a decade ago. During this time, measurement techniques have advanced at a rapid pace. The large statistics collected and new advanced methods allow us to finally test the top quark's place in the Standard Model. I will present the state-of-the-art in measuring top quark production, which includes the two most precise measurements of the top quark cross section in the world. I will also present the combined top quark cross section for several measurements in all channels at CDF. The result is the most precise determination of the rate of top quark production to date. In addtion to discussing the top cross section, I present a measurement of the forward backward asymmetry in top production. This measurement is a test of discrete symmetries at very high energy, which has recently received a sizable amount of attention because of an unexpectedly large measured value.
Tuesday September 29 at 1:40pm
Sarah Eno
University of Maryland
Early searches for exotic physics, beyond the standard model, with CMS (slides pdf)
The LHC is scheduled to commence running this fall, and should at sometime during the run become the world's new high-energy frontier. Many models of physics beyond the standard model, such as those with extra dimensions, can produce spectacular "exotic" signatures with large rates that could be detected with even a small amount of high-energy data. In this talk, I discuss preparations and projected reach for these searches from the CMS collaboration for the upcoming run.
Tuesday October 6 at 1:40pm
Rutgers University
Direct measurement of the W boson production charge asymmetry at CDF (slides pdf)
I will present the first direct measurement of the W production charge asymmetry as a function of the W boson rapidity y_W in p-pbar collisions at the Tevatron. I use a sample of W->e nu events in data from 1 fb-1 of integrated luminosity collected using the CDF II detector. In the region | y_W | < 3.0, this measurement is capable of constraining the ratio of up- and down-quark momentum distributions in the proton more directly than in previous measurements of the asymmetry that are functions of the charged-lepton pseudorapidity.
Tuesday October 13 at 1:40pm
Gustaaf Brooijmans
Columbia University
Breaking the Electroweak Barrier: Novel Signatures at Hadron Colliders (pdf slides)
The search for physics beyond the standard model will be the main focus of the experiments at the LHC. We have precious little information on the nature of any new physics however, and will need to explore a large variety of signatures in our exploration of the multi-TeV energy domain. One interesting possibility is that new physics will manifest itself in the decays of heavy objects to top quarks or W and Z bosons. This will lead to novel experimental signatures which will be discussed in this seminar.
Tuesday October 27 at 3:30pm in A8 (colloquium)
Evelyn Thomson
University of Pennsylvania
Smashing particles at the High Energy Frontier (pdf slides)
Experimental particle physics seeks to understand the fundamental particles and interactions of the universe. I will present the status and future prospects of experimental knowledge for two of these particles: the top quark, the most massive fundamental particle with approximately the same mass as a gold nucleus comprised of 200 nucleons; and the Higgs boson, the most elusive particle as it has evaded detection for over forty years! The results that I will present are based on analysis of data from the current run of the CDF experiment at Fermilab, which began in 2001 and is expected to continue through 2010. In order to produce massive particles like the top quark, Einstein's famous relation E=mc2 tells us that a lot of energy is needed. Therefore, a beam of protons is accelerated to close to the speed of light and then brought into collision with another equally energetic beam moving in the opposite direction. These collisions occur 1.7 million times per second, and I will discuss how the debris from these collisions is examined for clues about the properties of particles like the top quark and the Higgs boson.

The prospects for the future are dominated by the next generation CERN Large Hadron Collider, located near Geneva in Switzerland, which will reach collision energies up to seven times higher than the Fermilab Tevatron. In preparation for the first year-long run of the Large Hadron Collider beginning in November 2009, I will also describe the commissioning of the Transition Radiation Tracker, an important part of the giant ATLAS experiment. The Transition Radiation Tracker is essentially a camera with 350,000 channels that takes 75 nano-second long snap-shots of the trajectories of electrically charged particles. The radius-of-curvature of a charged particle's trajectory in a strong magnetic field allows determination of the particle's momentum, while the 100 times brighter signal from transition radiation allows partial discrimination of the least massive charged particle, the electron, from other more massive charged particles.

Tuesday November 17 at 1:40pm
Paul Sorensen
Brookhaven National Laboratory
Recent results with the STAR detector at RHIC

Tuesday November 24 at 1:40pm
Justin Keung
University of Pennsylvania
Search for WZ in the lvbb final state at CDF (slides pdf)

Tuesday December 1 at 1:40pm
Valerie Halyo
Princeton University
CMS Luminosity Monitors and Standard Candles (slides pdf)

Tuesday December 8 at 1:40pm
Gabriel Orebi Gann
University of Pennsylvania
New results from SNO (slides pdf)

### Seminars in 2008

Friday January 11 1:30pm
Dr. Dmitri Tsbychev
State University of New York, Stony Brook
Looking for new physics in the Bs-meson system
Slides (pdf)
The D0 experiment at the Fermilab Tevatron collider has collected large samples of hadronic and semileptonic decays of Bs mesons, in which comprehensive studies were performed to search for evidence of physics beyond the Standard Model. We present the latest results on the measurement of mixing parameter dMs and the width difference between heavy and light Bs-meson states as well the latest results on indirect CP violation in the Bs meson system at D0.
Thursday January 17 1:30pm
Dr. Chunhui Chen
University of Maryland
The Measurement of CP Violation Parameter Beta and Search for the New Physics from Babar Experiment
Slides (pdf)
In the Standard Model, quark mass, their mixing and CP violation have a common origin, the spontaneous electroweak symmetry breaking due to the Higgs boson. Studying CP violation and flavor-changing interactions not only probes the electroweak scale, but also provides an excellent laboratory for us to search new physics beyond the Standard Model. In this talk, I will present the most recent measurements of CP violation in the B meson decays from Babar experiment. The main focus of the talk will be the determination of the Cabibbo-Kobayashi-Maskawa (CKM) phase: beta. I will also discuss the implication of the results of CP violation in B decays for the Standard Model and some of its extension.
Tuesday January 22 1:30pm
Dr. Eliot Lipeles
University of California, San Diego
The Search for the Higgs and Diboson Production at the Energy Frontier
Slides (pdf)
At the core of the standard model of particle physics is the mechanism of electroweak symmetry breaking. The key ingredient of this mechanism, the Higgs boson, has yet to be seen. I present a search for the Higgs decay to the WW final state and measurements diboson production which is sensitive to the electroweak symmetry breaking predictions for the couplings between gauge bosons.
Thursday January 24 1:30pm
Dr. Florencia Canelli
Fermi National Accelerator Laboratory
Towards an understanding of electroweak symmetry breaking
Slides (pdf)
The top quark offers a powerful window to understanding physics at the electroweak scale. Through the precision measurement of its mass, we are directed to the mass of the Higgs boson, the physical manifestation of the standard model explanation for electroweak symmetry breaking. Through its single-top production, as opposed to the more common QCD production, we learn about electroweak production of the heaviest quark, and we provide a stepping stone to Higgs boson production in the same topology. Through study of the top quark decay couplings, we test for new higher energy scale deviations from the standard model electroweak interaction. In this talk, I will highlight the rich physics of the top quark, and its significance in understanding electroweak scale physics.
Tuesday January 29 1:30pm
Dr. Alexandre Telnov
Princeton University
Recent progress in CP violation: New Physics under siege
Slides (pdf)
Just eight years ago, the dominant role of the Kobayashi-Maskawa mechanism of CP violation in low-energy flavor-changing processes was merely a credible hypothesis. Started in 1999, the asymmetric B-meson factories at SLAC and KEK rapidly established CP violation as one of the inalienable features of the Standard Model (SM) through the study of the B0 decays driven by the tree-level b -> c c-bar s transition. Then, they took advantage of their spectacular success in reaching luminosities well above the design values by unleashing an attack on the SM of unprecedented breadth, precision and vigor.
Indeed, nearly all SM extensions provide multiple new sources of CP and flavor violation, which in general could lead to significant deviations from SM predictions in B-meson decays. Particularly sensitive to New Physics are the processes driven by flavor-changing neutral currents (FCNCs), which are strongly suppressed in the SM by the small CKM angles and the GIM mechanism; various SM extensions would require highly specialized flavor structures to achieve similarly effective FCNC suppression. Any statistically significant deviation from the SM predictions would mean the end of Standard Model's reign; lack thereof provides unique information about TeV-scale physics and, with the increasing precision of B-factory measurements, greatly constrains the parameter spaces of the favorite SM extensions.
A brief historical and theoretical introduction to CP violation and its significance to cosmology will be followed by a review of the experimental techniques employed at B-meson factories to make precise measurements of CP-violating quantities and to search for signs of physics beyond the SM. We will review the measurements performed by the BaBar and Belle experiments where CP violation has been firmly established, and discuss how recent advances in harnessing the full particle-identification power of the BaBar detector have helped pave the way to the observation of CP violation in the time distribution of B0 -> pi+pi- decays and direct CP violation in B0 -> K+pi-. In conclusion, we will recap the current experimental status of CP violation and the Standard Model, and take a glimpse at their future.
Tuesday February 5 1:30pm
Dr. Andy Haas
Columbia University
The Search for the SM Higgs Boson at D0
Slides (pdf)
Discovery of the Higgs boson would verify the final piece of the Standard Model. The Higgs boson is needed to explain how the W and Z bosons of the weak force acquire mass and to consistently give masses to the fermions. Using the D0 detector at the Fermilab accelerator, our group is progressing in our hunt for this elusive new particle. Particular decay channels will be highlighted, and some of the advanced analysis methods and tools developed for the search will be discussed in detail. Finally, the projected sensitivity for the next two years and a few techniques that will help to achieve this sensitivity will be shown.
Tuesday 25 March 1:30pm
Wilson Fellow at Fermi National Accelerator Laboratory
From Collisions to Publication: A Higgs Story (Slides pdf)
For more than 30 years the Standard Model of Particle Physics provided a solid framework for explaining the experimental observations of the last decades. A fundamental piece is missing and that is the origin of mass. Within the Standard Model, the mass of fundamental particles is given by their interaction with the Higgs field. The quanta of this field is the Higgs boson. The experimental observation of the Higgs particle is an essential part of our particle physics program and may provide us with clues about new physics beyond the realm of the Standard Model. I will show the experimental progress towards this goal at CDF, one of the two experiments at Tevatron, the world's largest collider currently in operation. The presentation will overview all aspects of this progress, from detector and data collection improvements to new analysis strategies.
Tuesday 1 April 1:30pm
Dr. Chris Neu
University of Pennsylvania
Measurement of W+b-jets at CDF (pdf)

Tuesday 15 April 1:30pm
University of Pennsylvania
Tau leptons at CDF (pdf)
Tau leptons are unique in the Standard Model. Thanks to a large coupling to the Higgs boson, they might shed light on the electroweak symmetry breaking. Tau leptons are also an exciting window into New Physics. SUSY predicts abundance of taus in charged Higgs decays. Taus processes are enriched in Right-Left Symmetric Models with double charged Higgs, while new massive gauge bosons can undergo lepton flavor violating decays. CDF established its tau reconstruction technique measuring the W → τ ν and Z → τ+ τ- cross sections and it is now exploring the pp collisions at Tevatron looking for new phenomena. The challenge of reconstructing taus at hadron colliders and the latest results of tau physics at CDF are reported.
Thursday 17 April 4pm Room A8
Emeritus Professor James Cronin
University of Chicago
Study of the Highest Energy Cosmic Rays with the Pierre Auger Observatory
Tuesday 22 April 1:30pm
Professor Joe Boudreau
University of Pittsburgh
sin 2 βs at CDF
While CP violation in B0 and B+ decays has been extensively investigated at B-factories over the last decade, corresponding knowlege in the B0s system has been lacking. B0s mesons, which are not produced in B factories at the Upsilon(4S) are produced with large cross section at the Tevatron collider. Following the measurement of the B0s to B0s oscillation frequency in 2006, the CDF experiment has now investigated CP asymmetries in B0s meson decays. We report on the very first flavor-tagged analysis of about 2,000 B0s decays to J/ψ φ, reconstructed in 1.35/fb of data. This channel is sensitive not only to the width difference Delta Γ in the B0s system but also to to βs, the angle of the "squashed" (bs) unitarity triangle. We report a confidence region in the two dimensional space of 2βs and Delta Γ. The data is consistent with the standard model prediction at the 15% confidence level, corresponding to 1.5 Gaussian standard deviations.
Monday June 2 3W2 1:30pm
University of Oxford
Rare B decays at CDF
Monday June 16 3W2 1:15pm
Chunlei Liu
University of Pittsburgh
The measurement of a small angle -- Search for CP violation in B0s system at CDF
CKM mechanism has been established well since the first CP violation discovery in 1964. To search for New Physics, it's useful to compare tiny CP violation prediction from Standard Model with experimental result. The B0_s-> J/psi phi channel provides such an ideal place where the CP phase is predicted to be nearly zero. At CDF, we are able to reconstruct about 2000 signal events with 1.35 fb-1 data. The final result we obtained is a confidence region in the CP phase and decay width difference space which shows an intriguing deviation (1.5 sigma) of the Standard Model.
Thursday August 7 1:30pm
Mr. Joe Tuggle
University of Maryland
Searching for New Physics in Radiative Penguin Decays at BaBar

Friday August 8 1:30pm
Mr. Rustem Ospanov
University of Texas at Austin
A measurement of muon neutrino disappearance rate with the MINOS detectors and the NuMI neutrino beam

Monday August 11 3:30pm
Mr. Brandon Parks
Ohio State University
Search for the Standard Model Higgs Boson at CDF Run II

Tuesday August 12 3:30pm
Mr. Sourabh Dube
Rutgers University
Search for Supersymmetry at CDF using the Trilepton signature

Tuesday October 28 1:30pm
Sasha Pranko
Fermi National Accelerator Laboratory
Physics with Photons at CDF (slides pdf)
Photon production in hadronic interactions is one of the most common processes. In fact, high energy photons are only outnumbered by jets. They are also present in many well motivated theoretical models of new physics beyond the Standard Model. Measurements with final state photons have many advantages. Photons couple to any particles with electric charge. Being stable particles, they do not suffer a sensitivity loss from branching ratios. Photon's energy and direction are well measured. In my presentation, I will talk about photon reconstruction at CDF, including photon identification, fake rates, and background subtraction techniques. In the second part of my talk, I will focus on searches for new physics in final states involving photons, jets, and missing transverse energy.
Tuesday November 11 1:30pm
Edgar Carrera
Florida State University
Search for extra dimensions with a single photon and missing transverse energy at D0 (slides pdf)
The enormous amount of fine-tuning that the Standard Model requires to salvage its validity at higher energy regimes is one of the most embarrassing aspects of our ignorance about the physical laws of Nature. Theories with large extra dimensions (LED), where gravitons can escape our 3-dimensional world, have been proposed as an alternative method to solve this problem. As a test for these hypothetical space configurations, I will present a D0 search for the direct production of Kaluza Klein gravitons in association with single photons. Special emphasis will be given to photon identification and the difficult task of rejecting backgrounds to these final states.
Thursday November 13 1:30pm note in room 2C8
Mark Hartz
University of Pittsburgh
Measurement of the B_c Meson Lifetime at CDF Using B_c->J/psi+l+X Decays
The B_c meson is an unique laboratory for studying QCD since it consists of two heavy quarks and decays via the weak interaction, allowing for the study of the weak decay properties in the framework of non-relativistic QCD. I review a measurement of the B_c lifetime at CDF using semileptonic B_c decays to J/psi particles and leptons. The result is compared to previous measurements of the B_c lifetime, and the measured quantities are used while discussing possible constraints on the theoretical predictions of the lifetime.
Tuesday November 25 1:30pm
Mitch Newcomer
University of Pennsylvania
Upgrading the ATLAS Detector for Super LHC (pdf slides)
The Large Hadronic Collider (LHC) will begin operation in the spring of 2009. The Two large detector systems, ATLAS and CMS built to search for the Higgs Boson and explore the limits of the Standard Model are arguably the most complex instruments ever constructed, each exploiting the effort a nearly a thousand scientists and engineers and taking more than 10 years to design and build. These detectors were envisioned for a useful life of ten years at the expected luminosity of 10^33 protons/cm^2. An upgrade to the accelerator planned for 2015 will greatly enhance the reach for experimenters to explore rare processes by increasing the luminosity by a factor of ten. This higher rate will require upgrading several detector sub-systems in each major detector, improving their rate capability and increasing their radiation tolerance. It is hoped that the system upgrade can be accomplished in the next five to seven years by taking advantage of the experts and infrastructure developed to complete the first generation detectors. Penn's successful involvement the development of detector mounted front end electronics for the ATLAS detector has led to the opportunity to take a leading role in this upgrade. Work on the choice of technology, architecture and in the development of Front End Electronics for silicon strip and calorimeter electronics will be presented.
Tuesday December 2 1:30pm
Trevor Vickey
University of Wisconsin
Searching for New Physics in High-pT Di-tau Final States with the ATLAS Experiment at the LHC (slides pdf)
A number of non-Standard-Model physics processes can lead to events with tau lepton pairs in the final state. I discuss the potential for the ATLAS experiment at the Large Hadron Collider (LHC) to observe high-mass resonances that decay into two oppositely-charged taus. The prospects for discovering an extra gauge boson, $Z'$, with a mass between 600 and 2000 GeV are presented and the application of this study to graviton and heavy MSSM Higgs boson searches is also discussed.
Tuesday December 9 1:30pm
Abid Patwa
Brookhaven National Laboratory
Search for MSSM Higgs Boson Production in di-tau final states at D0 (slides pdf)
Recent results from the D0 Experiment at the Fermilab Tevatron collider are presented on the search for the production of neutral Higgs bosons decaying into di-tau final states. In particular, searches with integrated luminosities of up to 2.2 fb-1 of data are described in both the Higgs decaying into tau pairs as well as those produced in association with a b-quark. Since no significant excess is observed over the predicted backgrounds in either decay mode, limits on its production cross section times branching ratio are set for Higgs masses within the range from 90 to 300 GeV. The results are subsequently interpreted in the Minimal Supersymmetric Standard Model (MSSM) and regions in the (mA, tan(beta)) parameter space for different MSSM benchmark scenarios are excluded at the 95% C.L. Future prospects for measurements with increased integrated luminosities delivered by the Tevatron are also discussed.

### Seminars in 2007

Friday March 23
Teh Lee Cheng
Royal Holloway, London
Search for production of single top quarks via flavour-changing neutral currents with the ATLAS detector.
I present the search for anomalous production of single top quarks via flavour-changing neutral currents (FCNC) with the ATLAS detector at the LHC. The signal is u/c + g -> t. Top quark FCNC coupling with a gluon is extremely small according to the Standard Model. However, new physics models usually allow large enhancements to this coupling, which may can be many orders of magnitude larger. A cut-based analysis is developed and the result shows that, with an integrated luminosity of 10 fb-1, equivalent to one year of LHC running at a tenth of the design luminosity, ATLAS starts to reach the required sensitivity to test predictions of some of the new physics models.

Tuesday April 3
Peter Wagner
Texas A&M
Search for Heavy, Neutral, Long-Lived Particles that Decay to Photons at CDF
Searches for events with final state photons and missing transverse energy (MET) at collider experiments are sensitive to new physics from a wide variety of models including gauge mediated supersymmetry breaking (GMSB). In these models the lightest neutralino (chi_10) decays into a photon and a weakly interacting, stable gravitino that gives rise to MET by leaving the detector without depositing any energy. The observation of an ee+photon+photon+MET candidate event by the CDF experiment during Run I at the Fermilab Tevatron has increased the interest in experimental tests of this class of theories. Most subsequent searches have focused on promptly produced photons, however the chi_10 can have a lifetime on the order of nanoseconds or more. In this talk I present the results of the first search for heavy, long-lived particles that decay to photons at a hadron collider using the newly installed EMTiming system at CDF to identify chi_10 candidates by virtue of their producing photons with a "delayed" arrival time.

Tuesday April 10
Huaizhang Deng
University of Pennsylvania
Discovery of Solar Neutrino Oscillations

Monday April 16
Sasa Fratina
Jozef Stefan Institute
Measurement of CP Violation in B0 -> D+D- Decays
I will report on the recent measurements of the branching fraction and CP violation parameters in B0 -> D+D- decays. The decay time distribution of these decays is sensitive to the angle of the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix phi_1 (beta) and offers another opportunity to test the unitarity of the CKM mixing matrix and search for possible new physics contributions to these decays. The results to be shown are based on a large data sample of more than 500 x 10^6 BBbar pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find evidence of CP violation in B0 -> D+D- at the 4.1 sigma confidence level. While the result for the CP violation parameter S is consistent with expectations from other measurements, the value of the parameter A favors large direct CP violation at the 3.2 sigma confidence level, in contradiction to Standard Model expectations.

Tuesday April 17
Sylvie Brunet
University of Montreal
|Vub| measurements at BaBar
The BaBar experiment, located at the Stanford Linear Accelerator Center (SLAC), produces millions of B mesons. The decay of the B mesons can be used to measure many elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix, which quantifies the quarks' flavor changing probabilities. One of the important elements is |Vub|. Its value is not predicted by the Standard Model. Its measurement is a critical constraint on the Unitarity Triangle, and thus, on the Standard Model itself. Our knowledge of |Vub| comes from measurements of the small B -> Xu l nu decay rates where a "b" to "u" quark transition is present. The precision on |Vub| is limited in large part by the uncertainties in the non-perturbative QCD calculations (form-factor) that are used to extract |Vub| from the measured decay rates. In this talk, I will concentrate on the recent measurement of B -> pi0 l nu decays using semileptonic tags at BaBar. From this study, a total branching fraction and partial branching fractions in three bins of q^2, the invariant mass squared of the lepton-neutrino system are reported. This allows us to evaluate |Vub| and to compare the measured form-factor spectrum, in three bins of q^2 with different theoretical predictions. I will also summarize the state of the art of the |Vub| measurements obtained at the B factories.

Wednesday April 18
Hirohisa Tanaka
Princeton University
First Results from MiniBooNE

This seminar reports the initial results from a search for muon neutrino to electron neutrino oscillations by the MiniBooNE (Mini Booster Neutrino Experiment) Collaboration. MiniBooNE was motivated by the result from the LSND experiment which presented evidence for neutrino oscillations with a mass-squared difference of O(1 eV^2/c^4). The MiniBooNE experiment uses a high-intensity neutrino beam with an average energy of ~800 MeV produced by protons from the Booster accelerator at Fermilab. The detector is a 800 ton sphere of mineral oil instrumented with 1520 photomultiplier tubes positioned 540 meters from the production target. The detector identifies and classifies neutrino events via the Cherenkov and scintillation light produced by particles emerging from the neutrino interactions. The results of this analysis use the neutrino-mode data set corresponding to 5.58x10^20 protons on target.

Wednesday April 25 Fisher-Bennet Hall, 3340 Walnut
Franklin Medal Symposium
schedule
Monday April 30
Brian Connolly
Columbia University
Probing the High Energy Universe the Ultrahigh Energy Cosmic Rays
The High Resolution Fly's Eye Experiment (HiRes) in Utah is an air fluorescence telescope mapping the northern sky in cosmic rays at energies above 10^18 eV. From December 1999 to March 2006 HiRes operated in stereo mode, i.e. with two sites separated by 13 km to provide cosmic ray data of unprecedented quality of the northern sky. We focus on the latest results from the monocular and stereoscopic data concerning the primary chemical composition above 10^18 eV and the observation of the GZK cut-off.
Tuesday 18 September A5 3:15pm
Dr. Bernd Stelzer
University of California, Los Angeles
Search for Single Top Quark Production at CDF
Slides (ppt) and pdf (no animations)
In 1995, the CDF and D0 collaborations at the Tevatron collider at Fermilab discovered top quarks that were produced in pairs via the strong interaction. The top quark was measured to be the heaviest elementary particle of the Standard Model. Ten years after the top quark discovery, many things remain unknown about its properties. In this talk, I will present recent evidence for electroweak single top quark production. This alternative mechanism of producing top quarks at the Tevatron is experimentally very challenging to measure but allows the direct determination of the CKM matrix element |Vtb|.
Wednesday 17 October A2 3:30pm
Dr. Ulrich Husemann
Yale University
Search for Flavor-Changing Neutral Currents in Top Quark Decay at CDF
Slides (pdf)
Flavor changing neutral current (FCNC) interactions are heavily suppressed in the standard model of particle physics, but are expected to be enhanced in the presence of new physics. Searches for FCNC interactions are therefore excellent probes of physics beyond the standard model. The suppression of FCNC interactions is especially strong in the top quark sector. The standard model predicts branching fractions for top quark FCNC decays far below the reach of experiments at the Fermilab Tevatron and even at the Large Hadron Collider currently under construction at CERN. I will present the first search for the FCNC decay t→ Zq during Tevatron Run II using data recorded with the CDF II detector between March 2002 and September 2006.
Tuesday 30 October A5 3:15pm
Prof. Daniel McKinsey
Yale University
New results from the XENON10 dark matter search
Slides (pdf)
The XENON10 experiment is a search for dark matter in the form of Weakly Interacting Massive Particles (WIMPs). The XENON10 detector uses the simultaneous measurement of ionization and scintillation in liquid xenon to distinguish between nuclear recoils (due to WIMPs or fast neutrons) and electron recoils (due to gamma rays). Ionization electrons are extracted into the xenon vapor where they produce a large proportional scintillation signal in a grid assembly. Both prompt and proportional scintillation light are detected by PMT arrays on the top and bottom of the active liquid xenon volume. The distribution of proportional scintillation light in the top PMT array can be used to achieve xy position resolution, while the ionization drift time gives position resolution in the z direction. This allows the definition of a low-background fiducial volume. XENON10 was installed in the underground Gran Sasso National Laboratory in Italy in March 2006, and a blind analysis was performed on data acquired between November 2006 and February 2007. I will present the results of that analysis, which has resulted in the most sensitive limit to date on the spin-independent WIMP-nucleon scattering cross-section. I will also describe LUX, a new dark matter experiment using the same technology, planned for 2008-2009.
Tuesday 13 November A5 3:15pm
Dr. Conor Henderson
Massachusetts Institute of Technology
Global Search for New Physics at CDF
Slides (pdf)
The Standard Model of particle physics is widely believed to be incomplete, but as yet there are no clear indications as to what form the new electroweak scale physics might take. Rather than focusing on particular new physics scenarios, we present a new approach where the entire high transverse momentum data collected by the CDF detector at the Fermilab Tevatron are searched for discrepancies relative to the Standard Model prediction. A model-independent approach (Vista) considers the bulk features of the data, and a quasi-model-independent technique (Sleuth) focuses on the high-pT tails. Results of this global search for beyond Standard Model physics will be presented.
Tuesday 27 November A5 3:15pm
Prof. B. Lee Roberts
Boston University
Proposal for a new muon g-2 experiment
Slides (pdf)
The muon (g-2) experiment at the BNL AGS reached a relative precision of 0.5 parts per million on the muon anomalous magnetic moment. Thanks to recent data from electron-positron annihilation to hadrons, the standard-model prediction has reached the same level of precision. When compared, the two differ by 3.4 standard deviations. Since the muon anomaly is sensitive to a wide range of physics beyond the standard model, agreement or difference with the standard-model will be important in constraining interpretations of discoveries that will be made at the LHC. The experiment and theory will be reviewed, and possibilities for improving both values will be discussed, along with the implications for LHC data.
A recent review of theory and experiment can be found in hep-ph/0703049, published in Reports on Progress in Physics, {\bf 70}, (2007) 795-881 The non-standard model reach is discussed in arXiv:0705.4617 [hep-ph]
Tuesday 11 December 2N36 1:30pm
Prof. Gregorio Bernardi
LPNHE, Universities Paris VI and VII, France
Search for the Higgs boson at D0
Slides (pdf)
The Higgs boson is the only particle of the standard model which has not been discovered yet, but it might be the most important one. Indeed, it is through the Higgs mechanism that all massive fundamental particles are expected to acquire their mass. Hence the search for the Higgs boson has been one of the major activities of Elementary Particle Physicists during this last decade. In this seminar, we will introduce the physics of the Higgs boson and report on the experimental searches which are currently being done at the Tevatron by the D0 experiment, and on the combined results obtained by CDF and D0. We will conclude on the prospects of Higgs discovery in the coming years.

### Seminars in 2006

January 11 2006 - Department Colloquium
Young-Kee Kim
Co-spokesperson of CDF and new Deputy Director of Fermilab

University of Chicago
E=mc2 Opening Windows on the World
slides (pdf)

January 17 2006
Masahiro Morii
Harvard University
B physics beyond CP violation: Semileptonic B decays
slides (pdf)

January 24 2006
Carsten Krauss
Queens University
The PICASSO dark matter experiment
slides (ppt) (pdf)
February 7 2006 Penn-Princeton joint seminar @ Penn
Pier Oddone
Director of Fermi National Accelerator Laboratory
Fermilab and High Energy Physics

March 1 2006 - Department Colloquium - Primakoff Lecture
Paul Langacker
University of Pennsylvania
The Standard Model and Strings - Can They be Connected?
slides (pdf)
March 14 2006
Kyle Cranmer
Brookhaven National Laboratory
Prospects for the Higgs at the LHC
slides (pdf)
April 4 2006
Purdue University
Chargino and Neutralino in the Golden Channel at CDF
slides (pdf)
April 11 2006
Dave Casper
University of California, Irvine
A long-baseline oscillation experiment using a radioactive ion storage ring ("beta-beam")
slides (pdf)

April 25 2006
Veronica Sorin
Michigan State University
CDF Trigger System at World Record Luminosities & Test of Electric Charge of the Top Quark
slides (pdf)
May 2 2006
Richard Hughes
Ohio State University
GLAST: Science in Flight
slides (pdf)
May 3 2006 - Special Department Colloquium
Joe Kroll
University of Pennsylvania
Matter-Antimatter Transformations at 3 Trillion Hertz

May 9 2006
Karen Gibson
Carnegie-MellonUniversity
Measurement of Relative Fragmentation Fractions of B hadrons at CDF
slides (pdf)

September 11 2006
Katherine Copic
University of Michigan
A New Measurement of the Ratio of W and Z Production at CDF

Electroweak physics at Fermilab is entering an era of new precision. With benchmark analyses completed, we are investigating new approaches to get the most out of our expanding data samples. I will present a new method for measuring the ratio of W and Z production at the Tevatron's center-of-mass energy of 1.96 TeV. This measurement can be used to extract the indirect width of the W boson and, therefore, the CKM matrix elements. For this analysis, a combined sample of W and Z boson candidates is selected by requiring at least one charged lepton and low net hadronic activity. The Missing Transverse Energy spectrum of the events is used to infer the relative rate of W and Z bosons. I will show a preliminary measurement of this ratio using data collected with the CDF detector, and discuss future prospects.

September 12 2006
Alexander Brandt
DESY
Photoinjectors: Automated Signal Calibration of Probeless Resonators

The accelerating field inside photoinjectors is required to be stable in phase to less than one degree. Field-symmetry considerations as well as difficulties in routing channels for cooling water put the mounting of a field probe into question. An alternative is to deduce the field from the incident and reflected wave from the resonator, which demands for a precise calibration of the channels. In this presentation, basic resonator theory is illuminated in order to deduce a method for an automated determination of these parameters, which also provides detailed information about the coupling (beta) and nonlinear properties of the sensors. The procedure, based on the investigation of resonant circles has been successfully tested at the electron guns at FLASH and PITZ. It is currently being implemented into FPGA-based controller of the FLASH electron gun.

October 10 2006
Dr. Aart Heijboer
University of Pennsylvania
Observation of Strange Beauty Meson oscillations
We report the observation of Bs-Bsbar oscillations from a time-dependent measurement of the Bs-Bsbar oscillation frequency Delta ms. Using a data sample of 1 fb^-1 of p-pbar collisions at sqrt{s}=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron, we find signals of 5600 fully reconstructed hadronic Bs decays, 3100 partially reconstructed hadronic Bs decays, and 61500 partially reconstructed semileptonic Bs decays. We measure the probability as a function of proper decay time that the Bs decays with the same, or opposite, flavor as the flavor at production, and we find a signal for Bs-Bsbar oscillations. The probability that random fluctuations could produce a comparable signal is 8 X 10^-8, which exceeds 5 sigma significance. We measure Delta ms = 17.77 +- 0.10 (stat) +- 0.07 (syst) ps^-1 and extract |Vtd/Vts| = 0.2060 +- 0.0007 (exp) + 0.0081 - 0.0060 (theory).

November 7 2006
Daniel Sherman
Harvard University
Top Quark Pair Production at CDF

November 14 2006
Jovan Mitrevski
Columbia University
Search for Electroweak Top Quark Production at D0
Electroweak production of the top quark has many attractive features. One is that the cross section is proportional to |Vtb|^2 and thus provides a test of the CKM matrix^s 3-generation unitarity. The constraints on |Vtb| not assuming unitarity are weak. Another is that it provides a way to probe the V - A structure of the weak interaction. Because the top quark decays before it has time to hadronize, it retains its polarization information, making it available for study. Furthermore, because the top quark has such a large mass, close to the scale of electroweak symmetry breaking, one wonders if it has some special role in beyond the Standard Model physics. Studying the electroweak interaction in single top production is a good way to look for such beyond the Standard Model effects. In this seminar I will discuss the search for electroweak production of the top quark being undertaken by the D0 collaboration at Fermilab. I will discuss our selection criteria and background modeling, and I will focus in particular on the matrix element method analysis currently under way using 1 fb-1 of data.

November 16 2006
Princeton University
CP Violation in b -> d Penguins
Over the last few years, the B factories at SLAC, USA, and KEK, Japan, have verified the Cabbibo-Kobayashi-Maskawa mechanism of CP violation in the Standard Model through the study of tree-dominated decays of the B meson. The focus of the B factories has now shifted to the search for signatures of new physics beyond the Standard Model, particularly through the study of flavor-changing neutral currents, which proceed through "penguin" diagrams involving a virtual loop. These decays are suppressed in the Standard Model, increasing sensitivity to new-physics effects but decreasing branching fractions. Exploiting large and growing datasets, BaBar and Belle have made many measurements in the penguin decays where a b quark transitions to an s quark, observing hints of possible deviations from Standard Model expectations in CP-violating measurements. In this talk, I describe the observation and first CP asymmetry measurement in the corresponding gluonic b-to-d penguins, which are further suppressed in the Standard Model and have not been previously observed. The observation of the decays B->K0K0bar and B->K0barK+ opens a new sector of enquiry for the B factories. I will also describe the update to the BaBar muon detector using Limited Streamer Tube technology.

November 21 2006
Dr. Gabriella Sciola
MIT
Searching for New Physics in Rare B Decays
The study of CP violation at the B factories allows us to perform quantitative tests of the CP sector of the Standard Model. Accurate measurements of the sides and angles of the Unitarity Triangle determine the parameters rho and eta of the theory, while redundant measurements of the same quantities allow us to probe physics Beyond the Standard Model. The recent measurements of the B_s mixing frequency at the Tevatron have dramatically improved our knowledge of |V_td/V_ts|, the right side of the Unitarity Triangle. This opens up a new opportunity for probing New Physics through an independent determination of the same quantity. In this talk, I will discuss how such a measurement can be made using rare B decays, and show our recent results.

November 28 2006
Dr. Stan Majewski
Jefferson Lab
A concept of a dedicated PET imager for proton therapy facilities

November 29 2006
Alberto Belloni
MIT
Observation of Bs - Bsbar oscillations

The latest results on the measurement of the Bs-Bsbar oscillation frequency using 1 fb-1 of data from ppbar collisions with the CDF II detector at the Fermilab Tevatron are reported. The probability as a function of proper decay time that the Bs decays with the same, or opposite, flavor as its flavor at production, which is determined using opposite-side and same-side flavour identification methods, is measured. A signal consistent with Bs-Bsbar oscillations is found.

December 19 2006
James Degenhardt
University of Michigan
Recent Diboson Physics Results from the DZero Collaboration
Diboson physics is the regime of electroweak physics that concerns itself with the production of two gauge bosons. Diboson measurements allow for verification of the Standard Model, while at the same time searching for evidence of new physics by measuring the coupling strengths of gauge bosons to each other. The Tevatron, which is the highest energy particle accelerator in the world, has been a rich source of new diboson physics results. I will be presenting the latest diboson physics results from the DZero collaboration, including the first evidence for WZ production.

### Seminars in 2005

September 13 2005
Daniel Whiteson
University of Pennsylvania
Precision Top Quark Mass Measurement in the Dilepton channel at CDF
slides (pdf)

September 27 2005
Dan Akerib
Case Western Reserve University
Looking for WIMPs in the Galactic Halo: The Cryogenic Dark Matter Search
slides (pdf)

October 11 2005
Jason Nielsen
Lawrence Berkeley National Laboratory
Search for the standard model Higgs Boson
slides (pdf)

November 1 2005
Chris Ainsley
Cambridge University
CALICE: a high precision calorimeter for the ILC
slides (pdf)

November 8 2005- Penn-Princeton joint seminar @ Princeton
Joe Lykken
University of Chicago and FNAL
Is Particle Physics Ready for the LHC?
slides (pdf)

November 15 2005
Aart Heijboer
University of Pennsylvania
Search for Bs mixing at CDF
slides (pdf)

December 6 2005
Volker Braun
University of Pennsylvania
Recent developments in String Theory Group at Penn - A Heterotic Standard Model
slides (pdf)

### Seminars in 2004

Tuesday, January 13 2004 at 1:30 (2N36 DRL)
Huaizhang Deng
University of Pennsylvania
Final result of the muon g-2 experiement

Wednesday, January 21 2004 at 2:00 (2N36 DRL)
Columbia University
Future Measurements of sin^2 2theta_13 at Nuclear Reactors

Tuesday, March 16 2004 at 1:30 (2N36 DRL)
Christopher Stepaniak
University of Minnesota
Measurements of semileptonic B-meson decay at CLEO

Tuesday, March 30 2004 at 1:30 (2N36 DRL)
Dawn Williams
University of California at Los Angeles
From the Moon to the Mines: Radio Detection of EHE Neutrinos

Wednesday, April 7 2004 at 1:30 (3N6 DRL)
Veronique Boisvert
CERN
Holding the Weights of the Heavens: the ATLAS High Level Trigger

### Seminars in 2003

Tuesday, March 18 2003 at 1:30 (2N36 DRL)
Chris Walter
Boston University
Oscillation Results From The K2K Experiment

Tuesday, March 25 2003 at 1:30 (2N36 DRL)
Scott Oser
University of Pennsylvania
Solar Neutrinos And Beyond: Where Do We Stand?

Tuesday, April 1 2003 at 1:30 (2N36 DRL)
Huaizhang Deng
Yale University
Measurement of g-2

Tuesday, April 8 2003 at 4:00, DRL A7
Sasha Glazov
University of Chicago
Measurement of $\epsilon'/\epsilon$ by KTeV collaboration

Tuesday, April 29 2003 at 1:30, DRL 2N36
Evelyn Thomson
Ohio StateUniversity
Top Quark Physics at CDF

Tuesday, October 7 2003 at 1:30 (3N6 DRL)
Daniel Whiteson
University of California, Berkeley
The electron-muon final state at D0: Top quark production and exotic physics

### Seminars in 2002

Tuesday, Sep. 10 2002 at 1:30 (2N36 DRL)
Fred Gray
University of Illinois-Urbana-Champaign
Measuring and Interpreting the Anomalous Magnetic Moment of the Muon

Tuesday, Nov. 5 2002 at 1:30 (2N36 DRL)
Daniel McKinsey
Princeton University
CLEAN: Cryogenic Low Energy Astrophysics with Neon

Tuesday, Nov. 26 2002 at 1:30 (2N36 DRL)
Brian Humensky
Princeton University
SLAC E-158: A Precision Measurement of Parity Violation in Moller Scattering

Tuesday, Dec. 3 2002 at 1:30 (2N36 DRL)
Roman Fleysher
NYU
Search for Gamma Ray Emission from Galactic Plane with Milagro

### Seminars in 2001

Tuesday Feb. 6 2001 at 1:30
Jon Urheim
University of Minnesota
Status of MINOS

Wednesday Feb. 14 2001 at 1:30
Joseph Formaggio
Columbia University
Searching High and Low for Exotic Particles at NuTeV

Friday, Feb. 23 2001 at 2:00 (2N36 DRL)
Akira Konaka
TRIUMF
A 2nd generation long baseline neutrino experiment - Neutrino program at JHF

Tuesday Feb. 27 2001 at 1:30
Dieter Zeppenfeld
University of Wisconsin
Weak Boson Fusion: A Tool for Higgs Boson Studies at the LHC

Monday Mar. 5 2001 at 12:45
Jordan Goodman
University of Maryland
New Results from Milagro

Tuesday, Mar. 2001 at 1:30
Tao Han
University of Wisconsin
Higgs/SUSY Searches at Future Colliders

Monday Mar. 26 2001 at 12:45
Viktor Zacekv
University of Montreal
Search for Neutralino Dark Matter and the PICASSO Project

Tuesday Apr. 10 2001 at 1:30
Sven Heinemeyer
Theoretical and experimental implications of the possible observation of Higgs bosons at LEP

Tuesday Apr 24 2001 at 1:30
Cenap Ozben
Brookhaven National Laboratory
Precise measurement of the positive muon anomalous magnetic moment at BNL

Tuesday May 1 2001 at 1:30
George Redlinger
Brookhaven National Laboratory
Probing the Unitarity Triangle with Rare K Decays

### Seminars in 2000

Tuesday Jan. 18 2000 1:30
Scott Oser
University of Chicago
Closing the Gap: First Results from STACEE

Tuesday Feb. 15 2000 1:30
Glenn Horton-Smith
Tohoku University, Japan
Introduction to KamLAND, the 1-kT Liquid scintillator
Anti-Neutrino Detector at Kamioka

Tuesday Feb. 22 2000 1:30
Artur Barczyk
ETH-Zurich
Measurement of W Boson Properties with the L3 experiment at LEP

Monday Feb. 28 2000 1:00
Kael Hanson
University of Michigan
A Measurement of the Neutrino-Induced Muon Flux at the MACRO Detector

Tuesday Feb. 29 2000 1:30
Klaus Rabbertz
Aachen
Event Shapes and Power Corrections in ep DIS

Monday Apr. 10 2000 3:30
Jens Erler
University of Pennsylvania
Is there a hint for a new Z boson in the precision data?

Friday Apr. 28 2000 1:00
Sherri Towers
Carleton Institute for Physics, Ottawa, Canada
Really Strange Tau Physics

Tuesday Nov. 7 2000 at 1:30
Hal Evans
Columbia University
B-Physics at Dzero (it's not just production any more)

Tuesday Nov. 14 2000 at 1:30
Paul Langacker
Penn
Electroweak Physics at LEP

Tuesday Nov. 21 2000 at 1:30
Penn
Recent Results from BABAR

Monday Dec. 4 2000 at 12:45
Kazuo Abe
KEK
Recent Results from BELLE

Tuesday Dec. 12 2000 at 1:30
Frank Paige
Brookhaven National Laboratory
Physics at a 500 GeV Linear Collider

Monday Dec. 18 2000 at 12:45
Chris Tully
Princeton University
Status of LEP-wide Higgs Searches

### Seminars in 1999

Feb. 2 1999
Josh Klein
University of Pennsylvania
Sudbury Neutrino Observatory: Current Status

Feb. 5 1999 AT 1:00
Mary Anne Cummings
Northern Illinois University
Top Quark Production in the All-Jet Channel at D0
and/or
Radiocoherence and Neutrino Physics

Feb. 8 1999 AT 1:00
Jean Duboscq
Ohio State University
The Tau Neutrino Mass Limit at CLEO and Elsewhere

Mar. 2 1999 at 1:30
Amit Lath
Rutgers University
Recent Results on Rare Processes and New Physics from KTeV

Friday, March 5 1999 at 1:30
Aaron Dominquez
CERN
Higgs searches at L3 using the 189 GeV data

Mar. 16 1999 at 1:30
University of Virginia
New Results from KTeV on Time Reversal Violation

Mar. 30 1999 at 1:30
Ikaros Bigi
University of Indiana
The Brown Muck of Beauty -- The Beauty of the Brown Muck

Thursday, Apr. 22 1999 1:00 3N6 DRL
John Beacom
Caltech
Neutrinos from the Next Galactic Supernova

Monday Sep. 13 1999 AT 4:00
Kate Frame
Michigan State University
A New Jet Finding Algorithm For Hadron Colliders

MONDAY Oct. 11 1999 at 1:30 3N6 DRL
Jim Hill
SUNY/Stony Brook
First Data from the K2K Experiment

Tuesday Oct. 19 1999 at 1:30
Yongsheng Gao
Harvard University
Observation of B --> Pseudo-scalar and vector meson Decays at CLEO

Tuesday Nov. 2 1999 at 1:30
Wasiq Bokhari
University of Pennsylvania
Status of Higgs Boson Searches at the Tevatron

Tuesday Nov. 9 1999 at 1:30
Joao Guimaraes da Costa
University of Michigan
b' Quark: The Next Generation

Thursday Nov. 11 1999 at 1:00 in 2N36 DRL
George Hou
National Taiwan University
Constraints on Gamma in the Unitarity Triangle

### Seminars in 1998

Jan 27 1998
George Smith
Yacht Apogee (Israel)
The History and Current Status of the CCD

Feb 9 1998
Rene Ong
University of Chicago
The Solar Tower Atmospheric Cherenkov Effect Experiment

Feb 10 1998
Jesse Stone
Princeton
K -> pi nu nu

Feb 17 1998
Mark Oreglia
University of Chicago
Results from the 183 GeV Running of OPAL

Feb 18 1998, 2pm
Chris Mindas
Princeton
K+ -> mu+ pi0 nu decays

Mar 31 1998 2:00 pm
Ed Kearns
Boston University

Apr 7 1998
Jim Beatty
Pennsylvania State University
Status of the Pierre Auger Project

Apr 14 1998
Tom Devlin
Rutgers University
Observation of the B_c Meson

Apr 28 1998
Kirk McDonald
Princeton University
The Physics of a Muon Collider

Oct 27 1998
George W.S. Hou
Brookhaven National Lab./National Taiwan University
West Indies, or New Continent--CP Violation at B Factories
(A phenomenological talk prepared for experimentalists.)

November 3 1998
Kate Scholberg
Boston University
The International Supernova Neutrino Alert Network

December 1 1998
Richard Steinberg
Drexel University
The CHOOZ Experiment

### Seminars in 1997

Oct 6 1997
Eric Prebys
Princeton University
SLAC E-144: Results from Sparking the Vacuum

Oct 13 1997
Tim Bolton
Kansas State University
Electroweak Physics with the NuTeV Detector at Fermilab

Nov 3 1997
Samim Erhan
UCLA
B Physics in the 21st Century

Nov 17 1997
David Stuart
Fermilab
The Search for New Phenomena at CDF

Nov 24 1997
Steven Ritz
Columbia University
The GLAST Experiment

Dec 1 1997
Andrew Bazarko
Princeton University
K --> pi nu nu

Dec 8 1997
Young-Kee Kim
UC-Berkeley
Precision Tests of the Electroweak Interaction from Hadron Colliders