High Energy Physics Seminars History
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, March 3, 2021
4:00 PM
Online, Room via Zoom
"Mu2e: A New Charged Lepton Flavor Violation Experiment: Muon-Electron Conversion at Sensitivity < 10-16"
Robert Bernstein , Fermi National Lab
[Host: Craig Group]
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. The conversion process results in a monochromatic electron with an energy slightly below the muon rest mass. Mu2e will improve the previous measurement by four orders of magnitude using a new technique, reaching a SES (single event sensitivity) of 3 x 10^{-17} on the conversion rate, and a discovery at 2 x 10^{-16}. The experiment will reach mass scales of nearly 10^4 TeV, far beyond the direct reach of colliders. The experiment is 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 with our first physics run in early 2025.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, February 3, 2021
4:00 PM
Online, Room via Zoom
"Reaching for the stars with CNO solar neutrinos"
Zara Bagdasarian , UC, Berkeley
[Host: Craig Dukes]
The prime energy producer in the sun is the fusion of hydrogen to form helium. However, there is more than one way for this fusion to takeplace: for stars the size of the sun or smaller, the proton-proton (pp) chain reactions dominate (~99%), while in heavier stars, the carbon-nitrogen-oxygen (CNO) cycle is expected to play a more important role. Not only these fusion reactions would not have been possible without the emission of neutrinos, neutrinos are the only way to directly access the processes in the core of the sun.
Borexino experiment, located at the Laboratori Nazionali del Gran Sasso, was built with a primary goal of the Be7 solar neutrinos (part of pp chain) detection. In more than a decade of data taking, Borexino has not only demonstrated the unprecedentedly high sensitivity towards Be7 solar neutrinos (<3%) but performed a comprehensive study of low-energy neutrinos from the complete pp-chain. After a number of developments in both hardware and software, Borexino has presented the first experimental evidence of the up-to-now elusive CNO fusion cycle in the Sun. The absence of the CNO neutrinos signal is disfavoured by the Borexino experiment at 5σ.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, January 20, 2021
4:00 PM
Online, Room via Zoom
"Search for resonant decays to neutral Standard Models Bosons and MET with the CMS Detector, and the CMS Hadron Calorimeter Upgrade"
Grace Cummings , University of Virginia - Department of Physics
[Host: Bob Hirosky]
Direct decays of proposed heavy force mediator particles to standard model leptons
have been largely excluded by past LHC searches, challenging theorists to explore more complex
decay chains. We begin our search with a framework model of a Leptophobic Z' cascading to a
pair anomalons, new Beyond the Standard Model fermions. These heavy intermediate particles decay in turn to neutral standard model bosons and a stable anomalon, which appears in the Compact Muon Solenoid (CMS) detector as missing transverse momentum (pT-miss). From a model independent point of view, this topology creates an interesting structure with a resonantly produced particle cascading to a final state with 2 missing particles, with each level of the cascade including new particles with unknown masses. To turn this into a bump hunt for the resonant particle, we employ Recursive Jigsaw Reconstruction (RJR), a rule-based methodology to systematically reduce degrees of freedom, allowing for the calculation of mass estimators at each level of our decay chain. RJR is an example of how analysis tools are evolving to be sensitive to the most well-hidden of new physics, and the detectors are doing the same. I will also give an overview of the Phase I upgrade to the CMS Hadronic Calorimeter.
[Host: Chris Neu]
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, January 6, 2021
4:00 PM
Online, Room via Zoom
"Low-Mass Dijet Resonance Search with Calo-Scouting Techniques using CMS Run-II Data at sqrt(s)=13 TeV and, the Studies on Improvements of the CMS Detector "
Ali Eren Simsek , Cukurova University
[Host: Chris Neu]
Physics models that allow the Standard Model to spread over a larger area often require new particles that attached to quarks and gluons and decay to dijets. The natural width of the resonances in the dijet mass spectrum (mjj) increases with coupling, and may vary from narrow resonance to wide resonance compared to experimental resolution. For example, in a model where DM (Dark Matter) particles are attached to quarks through a "DM Mediator" and the mediator can be decay to a pair of DM particles or a pair of jets and therefore can be observed as a dijet resonance. In this seminar, searches are presented for resonances with mass between 0.6 and 1.8 TeV decaying to dijet final states in proton-proton collisions at sqrt(s)=13 TeV. The searches are performed with dijets that are reconstructed from calorimeter information in the trigger using data corresponding to an integrated luminosity of 122 /fb. The dijet mass spectrum is compared to a smooth parameterization of the QCD background and simulations of resonance signals decaying into parton pairs. Upper limits at 95% CL are presented on the production cross section of narrow quark-quark, quark-gluon and gluon-gluon resonances. This seminar also includes the studies on minor and major CMS upgrades such as HGCAL (High-Granularity Calorimeter) MIP (Minimum Ionizing Particle) Calibration Analysis with test-beam data and full ~607 meters of SPS (Super Proton Synchrotron) H2 Beamline simulation using Geant4 Beamline for 2018 HGCAL test-beam.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, December 2, 2020
4:00 PM
Physics Building, Room 204
Standard Model(SM) is a very successful theory in particle physics, which can explain most of the high energy experiment. However, still there are many open questions for the SM, such as dark matter, dark energy and gravity interaction. One of the main goal for both ATLAS and CMS detector in LHC is to search for the new physics beyond the Standard model, to give us some hint for those open questions. This talk presents two analyses for the new physics search: 1: Search for the heavy resonance Z' decaying into a Higgs boson and a photon; 2: Search for lepton flavor violation Z->emu decay. Both of these two analyses use proton proton collision data set collected by ATLAS detector from 2015 to 2018. This talk also covers some upgrade study for the ATLAS inner tracker.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Monday, November 23, 2020
4:00 PM
Online, Room via Zoom
"Determination of the Jet Energy Scale Corrections for the Low pT Jets at root(s) = 13 TeV in CMS and Activities at HCAL Phase-1 Upgrade"
Zuhal Seyma Demiroglu , Cukurova University
[Host: Chris Neu]
The most abundant objects produced in high-energy proton-proton collisions at the LHC are jets which are reconstructed from topologically associated energy depositions in calorimeter cells, charged-particle tracks, or simulated particles. Ideally, jets are corrected due to the intrinsic limitations of the detector system. In CMS, reconstructed jets are calibrated by using a factorized approach. This seminar will present two analyses related to jet energy scale corrections focus on the low pT region. The first part of the talk is dedicated to the Monte Carlo (MC) truth jet energy corrections for no pileup QCD PYTHIA8 sample. The study is performed using the anti-kT clustering algorithm with a distance parameter R = 0.4 in the pseudorapidity range |η| < 5.191 for jet transverse momentum 10 < pT < 905 GeV. The second part presents the calibration of the jet energy scale with respect to residual differences between data and simulation after simulation-based pre-calibrations are applied. In this analysis, low pile-up data collected by the CMS experiment in 2015 at a center-of-mass energy of 13 TeV are used. The correction factors depending on jet pT and η are derived by using two different methods based on the dijet final states in the region of |η| < 5.191 pseudorapidity and 20 < pT < 114 GeV. This will make an important contribution to the physics analysis to be performed using the low pT jets. In addition, previous physics analysis, and activities at the Phase-1 Upgrade of the CMS Hadron Calorimeter will be also presented.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, November 18, 2020
4:00 PM
Online, Room via Zoom
"Measurement of the cross section of top quark pairs in association with a photon in lepton + jets events at root(s) = 13 TeV with CMS full Run II data"
Nabin Poudyal , Wayne State University
[Host: Chris Neu]
The production cross-section of top quark pairs in association with a photon is measured in lepton + jets final state events during proton-proton collisions at LHC 13TeV energy using the full Run II data collected by CMS with the total integrated luminosity of 137 fb-1. The study of top quark pair production in association with a photon provides us with important information on top quark electroweak coupling. It is also sensitive to beyond the Standard Model. The analysis is done in a semi leptonic decay channel with a well isolated high Pt lepton, at least four jets from the hadronization of quarks, and an isolated photon. The photons may be emitted from initial state radiation, top quarks, and decay products of top quarks. The simultaneous maximum likelihood fitting of several control regions and kinematic observables is done extensively and carefully to distinguish the ttγ signal process from various backgrounds. The inclusive cross section of ttγ process is measured for a photon with the transverse momentum Pt ≥ 20 GeV.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, November 11, 2020
4:00 PM
Online, Room via Zoom
"Search for Displaced Leptons & Beam Tests for the CMS Pixel Detector Upgrade"
Bryan Cardwell , Ohio State University
[Host: Chris Neu]
I present the two foci of my graduate research: a search for long-lived beyond-the-Standard-Model particles and R&D for the high-luminosity upgrade of the CMS pixel detector. First, I discuss the search for long-lived particles, which is performed in over 100 fb-1 of 13 TeV proton-proton collision data collected by the CMS experiment and uses electron and muon transverse impact parameter to identify displaced leptons, an exotic signature that is not covered by traditional analyses. In the second portion of the talk, I discuss the upcoming CMS silicon pixel detector upgrade, which will result in significant improvements in both functionality and radiation tolerance to stand up to the unprecedented particle flux and radiation dose of the High-Luminosity LHC. The discussion will focus on beam tests of prototype sensors and readout chips performed at the Fermilab Test Beam Facility.
Join Zoom Meeting:
https://us02web.zoom.us/j/81175477993?pwd=MWlvQVI4NlE4d2FBQjNrdEpsZHJRUT09
Thursday, November 5, 2020
4:00 PM
Online, Room via Zoom
"Gravitational wave memory effects in Brans-Dicke theory"
Shammi Tahura , University of Virginia - Department of Physics
[Host: Kent Yagi]
When gravitational waves pass through observers located far away from the source, they cause oscillatory distortions of the separations among the observers. There is one more interesting phenomenon that the gravitational waves can create lasting relative displacements of the observers, which is called the gravitational wave memory effect. Such effects are closely related to infrared properties of gravity and other massless field theories, including their asymptotic symmetries and conserved quantities. In this talk, I will present the Brans-Dicke theory in Bondi-Sachs form, discussing asymptotic symmetries, conserved charges, and the gravitational wave memory effects.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, November 4, 2020
3:30 PM
Online, Room via Zoom
"Latest Oscillation Results Combining Neutrino and Antineutrino Data from the NOvA Experiment"
Michael Baird , University of Virginia - Department of Physics
[Host: Craig Dukes]
The NOvA experiment is a long-baseline neutrino oscillation experiment that uses the NuMI beam from Fermilab to detect both electron and muon flavored neutrinos in a Near Detector, located at Fermilab, and a Far Detector, located at Ash River, Minnesota. NOvA’s primary physics goals include precision measurements of neutrino oscillation parameters, such as θ23 and the atmospheric mass- squared splitting, along with probes of the mass hierarchy and the CP violating phase. This talk will present the latest NOvA results using a combined neutrino and anti-neutrino dataset based on a beam exposure of approximately 13 × 1020 protons-on-target in each dataset.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, October 28, 2020
4:00 PM
Online, Room via Zoom
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, October 14, 2020
4:00 PM
via Zoom, Room Online
"Digital archaeology: Tomographic Imaging of the Great Pyramid of Giza"
Alan Bross , Fermilab
[Host: Craig Dukes]
In 1970 L. Alvarez et al. reported on the first experiment to use cosmic-ray muons to investigate the interior of a very large structure. That structure was Khafre's Pyramid at Giza. In 2017, the Scan Pyramids team reported on the discovery of a new large void in the Great Pyramid (Khufu). Although they used modern equipment, their system was not much larger than the one used by Alvarez's team. In order for the technique of cosmic-ray muon tomography to be able to answer detailed questions regarding the core structure of these enormous creations, a new approach must be taken. The Exploring the Great Pyramid (EGP) Mission will use detector technology currently deployed in high-energy physics experiments to field very large muon telescopes outside of the Great Pyramid. This will allow for a high-resolution study of almost all of its internal structure. It will go beyond simply looking for voids, but will potentially yield new information on the building techniques used to construct the Great Pyramid. In this talk, I will review previous experiments, describe in detail the techniques the EGP Mission proposes to use and present preliminary simulation results.
"The Design, Fabrication, and Performance of a Large-Area, HighEfficiency Cosmic Ray Veto Detector for the Mu2e Experiment at Fermilab "
Steven Boi , University of Virginia - Department of Physics
[Host: Craig Dukes]
The Muon-to-Electron-Conversion (Mu2e) Experiment is a high-precision, intensity-frontier experiment being developed at Fermilab which will search for coherent, neutrino-less muon to electron conversion in the presence of an atomic nucleus. Such a process would exhibit charged lepton flavor violation (CLFV), which has not yet been observed. Continuing the search for CLFV, Mu2e will improve the sensitivity by four orders of magnitude over the present limits. In the search for beyond the standard model (BSM) physics, Mu2e is uniquely sensitive to a wide range of models by indirectly probing mass scales up to the energy scale of 104 TeV. While muon-to-electron-conversion is permissible through neutrino oscillations in an extension of the standard model, the rate is extremely low at about one event in 1054. By design, the background for the experiment will be well-understood and kept at a sub-event level, which results in the observation of muon-to-electron conversion as direct confirmation of BSM physics. The largest background comes from processes initiated by cosmic-ray muons, which will produce approximately one CLFV-like event per day. In order to reduce this rate to less than one event over the lifetime of the experiment a large and highly efficient cosmic ray veto (CRV) detector is needed. The CRV will cover the experimental apparatus with an area of approximately 330 m2. The overall efficiency must be no les than 99.99%, a requirement that must be maintained in the presence of intense backgrounds produced by proton and muon beams. The detector employs long scintillator strips with embedded wavelength shifting fibers, read out using silicon photomultipliers. Key features of the talk involve the design, fabrication, and performance of the CRV, along with an overview of the Mu2e experiment.
Wednesday, February 19, 2020
3:30 PM
Physics Building, Room 204
[Host: Peter Arnold]
Wednesday, February 12, 2020
3:30 PM
Physics Building, Room 204
[Host: Peter Arnold]
Wednesday, February 5, 2020
3:30 PM
Physics Building, Room 204
[Host: Peter Arnold]
Wednesday, January 29, 2020
3:30 PM
Physics Building, Room 204
[Host: Peter Arnold]
"Precision timing with the CMS MIP timing detector and search for new particle production at the LHC "
Matt Joyce , University of Virginia - Department of Physics
[Host: Brad Cox]
The Compact Muon Solenoid (CMS) detector at the CERN Large Hadron Collider (LHC) is undergoing an extensive Phase II upgrade program to prepare for the challenging conditions of the High-Luminosity LHC (HL-LHC). In particular, a new timing layer will measure minimum ionizing particles (MIPs) with a time resolution of ~30ps and hermetic coverage up to a pseudo-rapidity of |η|=3. This MIP Timing Detector (MTD) will consist of a central barrel region based on LYSO:Ce crystals read out with SiPMs and two end-caps instrumented with radiation-tolerant Low Gain Avalanche Diodes. The precision time information from the MTD will reduce the effects of the high levels of pile-up expected at the HL-LHC and will bring new and unique capabilities to the CMS detector. The time information assigned to each track will enable the use of 4D reconstruction algorithms and will further discriminate interaction vertices within the same bunch crossing to recover the track purity of vertices in current LHC conditions. We present motivations for precision timing at the HL-LHC and the ongoing MTD R&D targeting enhanced timing performance and radiation tolerance for the barrel layer components. We will also describe the progress of our search for new physics in final states with two photons and missing transverse energy using the full Run2 dataset.
Wednesday, January 22, 2020
3:30 PM
Physics Building, Room 204
[Host: Peter Arnold]
Wednesday, January 15, 2020
3:30 PM
Physics Building, Room 204
[Host: Peter Arnold]
Thursday, November 14, 2019
4:00 PM
Physics Building, Room 204
"Light in the Dark-Opening a new window to the Dark Sector "
Ruth Pottgen , Lund University
[Host: Craig Dukes]
The origin and observed abundance of Dark Matter in the Universe can be explained elegantly by the thermal freeze-out mechanism, leading to a preferred mass range of the Dark Matter particles in the MeV-TeV region. The GeV-TeV mass range is being explored intensely by the variety of experiments searching for Weakly Interacting Massive Particles. The sub-GeV region, however, in which the masses of most of the building blocks of stable matter lie, is hardly being tested experimentally to date.
This mass range occurs naturally in Hidden Sector Dark Matter models. The Light Dark Matter eXperiment (LDMX) is a planned electron-beam fixed-target experiment, that has unique potential to conclusively test models for such light Dark Matter in the MeV to GeV range. This presentation will give an overview of the theoretical motivation, the main experimental challenges and how they are addressed as well as projected sensitivities.
"Searching for Dark Matter from the Lowest to the Highest Energies "
Bjoern Penning , Brandeis University
[Host: Bob Hirosky]
Dark Matter (DM) is a long standing puzzle in fundamental physics and goal of a diverse research program. In underground experiments we search for DM directly using lowest possible energy thresholds, at collider we seek to produce dark matter at the very highest energies, and with telescopes we look for telltale signatures in the cosmos. All these detection methods probe different parts of the possible parameter space. I will highlight status of existing and upcoming experiments including new direct detection experiments with world leading sensitivities to start data taking in early 2020. Finally we’ll discuss how to connect these approaches and how an interdisciplinary program bridging experimental frontiers can provide the most stringent constraints.
"CNN Jet Image Tagging: from top measurements to new physics searches"
Dr. Kevin Nash , Rutgers University
[Host: Chris Neu]
We detail the application of image recognition to jet tagging in CMS. The method is based on the CNN top tagging optimization seen in arXiv:1803.00107v1 and evolved to include additional color information, b tagging, and an adaptive zoom. Additionally, we demonstrate how this jet tagging network can be decorrelated from the mass of the progenitor jet, which allows for the possibility of tagging BSM objects. We study the impact on top tagging sensitivity, the data-simulation agreement, and the versatility of the network to accept more exotic signatures. Finally, we describe the application to the latest BSM physics searches.
Wednesday, July 24, 2019
3:30 PM
Physics Building, Room 204
An integral part of the proton spin puzzle are the contributions to the proton spin coming from quarks and gluons having very small values of the Bjorken x variable. These contributions are mostly beyond the reach of current experiments and are very hard to calculate numerically on the lattice. It appears that better theoretical understanding of quark and gluon helicity distributions at small x is needed to assess the amount of proton spin coming from this region. In my talk I will describe the recent theoretical work aimed at finding the small-x asymptotics of the quark and gluon helicity distributions, along with their orbital angular momenta (OAM). I will derive small-x evolution equation for helicity and solve them to find the small-x asymptotics of the parton helicity distributions and OAM. The results of this work can be compared to the data to be collected at the upcoming Electron-Ion Collider (EIC) and can also be used to extrapolate the small-x helicity distributions to be measured at EIC to even smaller values of x, thus constraining the proton spin coming from small x.
"Light ring stability in ultra-compact objects"
Pedro Cunha , University of Lisbon
[Host: Kent Yagi]
The following theorem is proven: axisymmetric, stationary solutions of the Einstein field equations formed from classical gravitational collapse of matter obeying the null energy condition, that are everywhere smooth and ultracompact (i.e., they have a light ring, a.k.a. circular photon orbit) must have at least two light rings, and one of them is stable. It has been argued that stable light rings generally lead to nonlinear spacetime instabilities. Thus this result implies that smooth, physically and dynamically reasonable ultracompact objects are not viable as observational alternatives to black holes whenever these instabilities occur on astrophysically short time scales. The proof of the theorem has two parts: (i) We show that light rings always come in pairs, one being a saddle point and the other a local extremum of an effective potential. This result follows from a topological argument based on the Brouwer degree of a continuous map, with no assumptions on the spacetime dynamics, and hence it is applicable to any metric gravity theory where photons follow null geodesics. (ii) Assuming Einstein’s equations, we show that the extremum is a local minimum of the potential (i.e., a stable light ring) if the energy-momentum tensor satisfies the null energy condition.
"The Exterior Spacetime of Relativistic Stars in Quadratic Gravity"
Alexander Saffer , Montana State University
[Host: Kent Yagi]
General Relativity (GR) has been the cornerstone of gravitational physics for a century. Over this time, numerous predictions and tests have strengthened the belief in GR as the foremost theory when discussing gravity. However, GR cannot in its present form be reconciled with either quantum mechanics, or many cosmological observations such as galactic rotation curves or the accelerated expansion of the universe. In an attempt to rectify these shortcomings, modified theories of gravity have been proposed. In this talk, I will present one of these theories and discuss my work in attempting to test its validity through the development of an exterior spacetime (metric) for a neutron star. From this, we expect to be able to develop a pulse profile which can be used, in conjunction with observations made of the x-ray flux of radiating neutron stars, to place constraints on the theory.
Wednesday, April 10, 2019
3:30 PM
Physics Building, Room 204
"Exploring light dark matter with the LDMX experiment"
Bertrand Echenard , Caltech
[Host: Craig Dukes]
Understanding the nature of dark matter is a central objective of modern science, and recent theoretical developments have highlighted the importance of extending current searches over a wider range of masses. The Light Dark Matter eXperiment (LDMX) has been propose to search for light dark matter and sub-GeV New Physics in fixed-target electron-nucleus collisions with unprecedented sensitivity. The experiment is based on a missing momentum technique, in which dark matter is emitted by electrons scattering in a thin target, resulting in large missing momentum and energy in the detector. This talk will discuss the motivation for light dark matter and describe the LDMX concept and its expected performance.
Wednesday, April 3, 2019
3:30 PM
Physics Building, Room 204
"Precise Measurement of the Ke2Kµ2 Branching Ratio and New Physics Search with a Stopped K+ Beam Experiment"
Dr. Tongtong Cao , Hampton University
[Host: Craig Group]
The J-PARC TREK/E36 experiment with a stopped K+ beam is designed to provide a more precise measurement of the branching ratio RK = Γ(K+ → e+ν)/Γ(K+ → µ+ν) than previous in-flight K+ decay experiments. RK is very precisely predicted by the Standard Model (SM) with an uncertainty of 4×10−4 and any deviation from this prediction would very clearly indicate the existence of new physics beyond the SM. Additionally, the experiment is searching for dark photons/light neutral bosons (A0), which could be associated with dark matter or explain the gµ-2 anomaly and the proton radius puzzle. In the experiment, a K+ beam was stopped by a scintillating fiber target, and charged decay products were momentum analyzed and tracked by a 12-sector superconducting toroidal magnetic spectrometer and multi-wire proportional chambers (MWPCs) combined with a photon calorimeter with a large solid angle (75% of 4π) and 3 different particle identification systems. In this talk, the status of the RK and A0 analyses is presented, and the MWPC calibration and tracking by a Kalman filter are reported. This work has been supported by awards DE-SC0003884 and DE-SC0013941 in U.S., NSERC in Canada, and Kaken-hi in Japan.
"Neutrino Physics from the PROSPECT Experiment"
Christopher White, Ph.D. , Illinois Institute of Technology
[Host: Craig Dukes]
PROSPECT, the Precision Oscillation and Spectrum Experiment, is a reactor antineutrino experiment designed to search for eV-scale sterile neutrinos and measure the spectrum of antineutrinos from highly-enriched 235U at the High Flux Isotope Reactor (HFIR). PROSPECT uses a 4-ton, segmented 6Li-doped liquid scintillator detector to make a high-resolution measurement of the prompt energy spectrum from inverse beta decay on protons. An optical and radioactive source calibration system integrated into the active detector volume is used to characterize the optical and energy response of all detector segments. I will discuss the calibration and characterization of the PROSPECT detector and report on PROSPECT’s first measurement of the energy spectrum associated with reactor antineutrinos.
Thursday, February 28, 2019
2:00 PM
Physics Building, Room 204
"A New QCD Facility at the M2 beam line of the CERN SPS (COMPASS++/AMBER)"
Oleg Denisov , COMPASS experiment
[Host: Dustin Keller]
Possibility to use high intensity secondary beams at the SPS M2 beam
line in combination with the world’s largest polarized target, liquid hydrogen,
liquid deuterium and various nuclear targets create a unique opportunity
for universal experimental facility to study previously unexplored aspects
of meson and nucleon structure, QCD dynamics and hadron spectroscopy.
High intensity hadron (pion dominated) beams already made COMPASS the
world leading facility for hadron spectroscopy and hadron structure
study through Drell-Yan production of di-muon pairs. High intensity
muon beams, previously used for unique semi-inclusive and exclusive
hard scattering programs, make possible proton radius measurement in
muon-proton elastic scattering and further development of polarized
exclusive hard scattering program.
Upgrades of the M2 beam line resulting in high intensity RF-separated
anti-proton- and kaon-beams would greatly expand the horizon of experimental
possibilities at CERN: hadron spectroscopy with kaon beam, studies
of transverse momentum dependent quark structure for protons, pions and
kaons, precise studies of nuclear effects and for the first time measurements
of kaon quark—gluon substructure.
[Host: Diana Vaman]
[Host: Diana Vaman]
[Host: Diana Vaman]
[Host: Diana Vaman]
[Host: Diana Vaman]
[Host: Diana Vaman]
TBA
"New results on the search for the elusive K_L→πνν ̅ with the KOTO detector "
Brian Beckford , University of Michigan
[Host: Craig Dukes]
The KOTO experiment was designed to observe and study the KL→πνν decay. The Standard Model (SM) prediction for the mode is 2.4 x 10-11
with a small theoretical uncertainty [1]. An experimental upper limit of 2.6 x 10-8
was set by the KEK E391a collaboration [2]. The rare “golden” decay is ideal for probing for physics beyond the standard model. A comparison of experimentally obtained results with SM calculations permits a test of the quark flavor region and provides a means to search for new physics.
The signature of the decay is a pair of photons from the π0 decay and no other detected particles. For the measurement of the energies and positions of the photons, KOTO uses a Cesium Iodide (CSI) electromagnetic calorimeter as the main detector, and hermetic veto counters to guarantee that there are no other detected particles.
KOTO’s initial data was collected in 2013 and achieved a similar sensitivity as E391a result [3]. Since then, we completed significant hardware upgrades and had additional physics runs in 2015 at beam powers of roughly 24-40 kW. This presentation will present new results from KOTO and its search of detecting KL→πνν.
The talk will highlight latest results on top quark physics at CMS employing pp collision data at a center-of-mass energy of 13 TeV. New results from other experiments and center of mass energies will also be discussed. With millions of top quarks already collected at the LHC top quark physics enters the precision era. Differential cross section measurements and top quark property measurements, in particular angular correlations, are challenging the Standard Model predictions. The intimate connection of the top quark to the Higgs Boson is scrutinized by highly precise direct measurements of the top quark mass, with alternative approaches entering the precision realm as well. The talk concludes with implications for the SM and an outlook towards the ultimate precision frontier at the high-luminosity phase of the LHC.
"Frontiers in Multi-Messenger Astrophysics at the interface of Numerical Relativity and Deep Learning"
Eliu Huerta , University of Illinois, Urbana-Champaign
[Host: Kent Yagi]
Gravitational wave observations with the LIGO and Virgo detectors from a succession of mergers of black holes are a triumph of experimental and theoretical physics, and data science. Similarly, the observation of two colliding neutron stars in gravitational waves and light heralds the era of Multi-Messenger Astrophysics. In this talk I outline a vision to drive innovation at the interface of gravitational wave astrophysics, large scale astronomical surveys, deep learning and large scale computing to address outstanding theoretical and data science challenges to realize the full potential of Multi-Messenger Astrophysics.
Wednesday, September 26, 2018
3:30 PM
Physics Building, Room 313
"Recent Results from the NOvA Neutrino Experiment"
Gavin Davies , Indiana University
[Host: Craig Group]
Neutrinos are abundant fundamental particles throughout the universe; second-most only to the photon. They undergo a phenomenon called neutrino oscillation whereby they change flavor from one type to another as they travel. The NOvA experiment seeks to elucidate further understanding of this phenomenon utilizing Fermilab's NuMI neutrino beam and two detectors to observe neutrino interactions: a 300 ton near detector underground at Fermilab, IL and a 14 kton far detector in Ash River, MN.
The NOvA experiment has recently produced updated neutrino oscillation measurements as well as its first antineutrino oscillation results and these are presented herein.
"Another addition to the U(1) jungle"
Triparno Bandyopadhyay , University of Calcutta
[Host: P.Q. Hung]
In a truly model independent approach we review the class of anomaly free U(1) extensions of the SM. Parametrising the extension in terms of three observable quantities, namely, MZ′, the Z-Z′ mixing angle (alphaZ) and the extra U(1) effective gauge coupling (g'), which absorb all model dependence, we proceed to draw exclusion contours in the parameter space. For the exclusion limits we use the latest LHC DY data, unitarity, and electron--muon-neutrino scattering data. The DY data turns out to be the most stringent, but the other two constraints have situational merits, as we discuss.
Wednesday, April 18, 2018
3:30 PM
Physics Building, Room 204
"Introduction to Applied Research Institute (ARI)"
Melissa Henriksen , Applied Research Institute
[Host: Nilanga Liyanage]
"A new Signal Processing Initiative to be Based at CERN"
Sebastian N. White , CERN
[Host: Craig Dukes]
The case for measuring the time of arrival of physics objects in the major LHC Experiments (CMS, ATLAS and TOTEM so far) has been building since it was first proposed roughly 5 years ago [?] and the LHC committee has already approved (in March 2018) for CMS to proceed to the next stage- the technical design. Along with this process there have been separately intense activities in establishing the physics performance benefits (through simulations) of this enhanced capability as well as laboratory and particle beam work to establish candidate technologies for the required level of timing precision (roughly 20-30 picosecond time resolution). A significant base for this sensor development work has been within the “PICOSEC” collaboration, which is not part of an LHC experiment but rather evolved within 2 CERN R&D groups following a “common fund proposal” by S. White and I. Giomataris in 2014. Over the past 3 years this project has accumulated a very carefully curated data set of high quality ( 2- 5 GHz BW and 20-40 GSa/s sampling) waveforms for the principal detector technologies (Silicon with internal Gain, MicroPattern Gas structures, Micro Channel Plate PMT) and achieved world records in timing precision for all of these sensor types. We propose to build from the productive collaboration with Wolfram Research during 2017 to use this large data set to guide the design of signal processing and digitizing electronics for fast timing, which is now capturing the attention of electronics groups in the US and Europe.
"An Indirect Search for Weakly Interactive Massive Particles in the Sun Using Upward-Going Muons in NOvA"
Cristiana Principato , UVA- Department of Physics
[Host: Craig Group]
We present an indirect search for particles produced via dark matter annihilations in the Sun using a dataset collected with an upward-going muon trigger at NOvA. Weakly Interactive Massive Particles are a theoretical non-baryonic form of Dark Matter. The nature of Dark Matter is one of the most interesting open questions in modern physics. Evidence for DM existence comes from cosmological observations but the discovery of its particle content has not been made yet. If DM particles can produce Standard Model particles through their interactions, indirect searches like the one described here could help shed light on the dark matter mystery.
Wednesday, February 21, 2018
3:30 PM
Physics Building, Room 204
Developments of the particle colliders over last 50 years have seen tremendous progress in both the energy of the collisions and the intensity of the colliding beams. In order to reach even higher collision energy many fundamental inventions in the colliders design have been achieved. Progress to even higher energies was strongly stimulated by physics interests in studying smaller and smaller distances and in creation of heavier and heavier elementary particles. Experiments at colliders required major breakthroughs in the particle detection methods in order to discover new particles such as c and t quarks, gluons, tau lepton, W, Z and Higgs bosons which completed currently expected set of elementary particles. Options for even higher energy colliders will be discussed, including their design parameters, acceleration principles as well as construction challenges. Such colliders are the only way to understand Nature at even smaller distances and create particles with higher masses than we can reach today.
"Deep Learning in High Energy Physics"
Daniel Whiteson , University of California at Irvine
[Host: Chris Neu]
Recent advances in artificial intelligence offer opportunities to disrupt the traditional techniques for data analysis in high energy physics. I will describe the new machine learning techniques, explain why they are particularly well suited for particle physics, and present selected results that demonstrate their new capabilities.
Monday, December 4, 2017
3:30 PM
Physics Building, Room 204
"A Tale of Two Theories: Searches for Higgs Pair Production with the ATLAS Detector"
Ben Tannenwald , Ohio State University
[Host: Chris Neu]
A new era in experimental particle physics began with the 2012 discovery of the Higgs boson by the ATLAS and CMS Collaborations. Multiple measurements have since shown the new boson possesses several properties (spin, parity, gauge couplings) consistent with the Standard Model, but many characteristics remain unknown. The nature of the Higgs self-coupling is currently unmeasured, and a precise understanding of this interaction would provide stringent new tests of the Standard Model Higgs sector. Searches for Higgs pair production have the power to confirm Standard Model predictions and help map the shape of the Higgs potential or provide a window into new physics beyond our current understanding. This seminar will summarize recent searches for Higgs pair production using the ATLAS detector. Constraints on exotic physics models will be presented and an outlook on future improvements will be discussed.
Tuesday, November 7, 2017
3:30 PM
Physics Building, Room 204
"Constraints on interacting dark matter from small scale structure"
Lan Nguyen , Notre Dame
[Host: Bob Hirosky]
In this talk we study the effects of interacting dark matter in the structure of galactic halos. The core-cusp problem remains as one of the unresolved challenges between observation and simulations in the standard CDM model for the formation of galaxies. Basically, the problem is that CDM simulations predict that the center of galactic dark matter halos contain a steep power-law mass density profile. However, observations of dwarf galaxies in the Local Group reveal a density profile consistent with a nearly at distribution of dark matter near the center. A number of solutions to this dilemma have been proposed. We discuss the possibility that the dark matter particles themselves self interact and scatter. The scattering of dark matter particles then can smooth out their profile in high-density regions. We also summarize a theoretical model as to how self- interacting dark matter may arise. We implement this form in simulations of self-interacting dark matter in models for galaxy formation and evolution. Constraints on properties of this form of self-interacting dark matter will be summarized.
[Host: Chris Neu]
Wednesday, October 11, 2017
3:30 PM
Physics Building, Room 204
[Host: Chris Neu]
"Is axion dark matter described by a classical scalar field?"
Elisa Todarello , University of Florida
[Host: Peter Arnold]
Axion dark matter has the unique property of having extremely high quantum occupancy. This may lead to think that axion dark matter can be described in terms of a classical field.
The usual equations for the linear growth of density perturbations in the cold dark matter fluid can be obtained from the classical description of a self-gravitating scalar field in the non-relativistic regime, with differences appearing only on scales smaller than a critical length.
However, axion dark matter is expected to thermalize through gravitational self-interactions and to form a Bose-Einstein condensate. I will argue that the classical field approximation is in general not valid for thermalizing quantum fields, even in the large occupancy regime, and discuss the different evolution of a homogeneous condensate in classical and quantum field theory.
[Host: Chris Neu]
[Host: Chris Neu]
"Progress on the Search for Magnetic Monopoles With the NOvA Far Detector"
Enhao Song , UVA-Department of Physics
[Host: E. Craig Dukes]
The NOνA experiment aims to study the mixing behavior of neutrinos and will attempt to resolve the neutrino mass hierarchy. The construction and instrumentation of the 14 kT far detector finished in 2014. Due to its surface proximity, large surface area, and continuous readout, the NOνA far detector is sensitive to the detection of magnetic monopoles which would be highly ionizing particles traversing the entire detector. In order to record candidate magnetic monopole events with high efficiency and low trigger rate, we have designed a software-based trigger to make decisions based on the data recorded by the detector. The decisions must be fast, have high efficiency, and a large rejection factor for the over 100,000 cosmic rays that course through the detector every second. In this seminar, we will describe the off-beam triggering system implemented for monopole detection together with a first look at the collected data.
"Second Numu Disappearance Results from the NOvA Experiment"
Michael Baird , UVA-Department of Physics
[Host: Craig Group]
In light of the Nobel Prize awarded for neutrino oscillations in 2015, it is an exciting time to be a part of a long-baseline neutrino oscillation experiment. NOvA is one such experiment based out of Fermilab National Accelerator Laboratory, which uses two liquid scintillator detectors, one at Fermilab (the ``near" detector) and a second 14 kton detector in northern Minnesota (the ``far" detector.) The primary physics goals of the NOvA experiment are to measure neutrino mixing parameters through both the numu disappearance and nue appearance channels using neutrinos from the newly upgraded NuMI beam line. This talk will present a summary of the NOvA experiment and the numu disappearance results, focusing on the implications for non-maximal mixing.
Thursday, April 27, 2017
1:00 PM
Physics Building, Room 313
"Origin of Long Lifetime of Band-Edge Charge Carriers in Organic-Inorganic Lead Iodide Perovskites"
Tianran Chen , UVA- Department of Physics
[Host: Seunghun Lee]
Long carrier lifetime is what makes hybrid organic-inorganic perovskites high performance photovoltaic materials. Several microscopic mechanisms behind the unusually long carrier lifetime have been proposed, such as formation of large polarons, Rashba effect, ferroelectric domains, and photon recycling. Here, we show that the screening of band-edge charge carriers by rotation of organic cation molecules can be a major contribution to the prolonged carrier lifetime. Our results reveal that the band-edge carrier lifetime increases when the system enters from a phase with lower rotational entropy to another phase with higher entropy. These results imply that the recombination of the photo-excited electrons and holes is suppressed by the screening, leading to the formation of polarons and thereby extending the lifetime. Thus, searching for organic-inorganic perovskites with high rotational entropy over a wide range of temperature may be a key to achieve superior solar cell performance.
Wednesday, April 26, 2017
3:30 PM
Physics Building, Room 204
"Emergent phenomena in correlated quantum materials"
Arun Paramekanti , University of Toronto
[Host: Israel Klich ]
The interplay of quantum mechanics and many-body interactions leads to remarkable emergent phenomena in crystalline solids, ranging from intricate magnetic orders to high temperature superconductivity to electronic analogues of liquid crystals. The quest to discover, understand, and control such phases of quantum materials has led to extensive research on transition metal oxides as well as ultracold atomic gases. I will present an overview of some ongoing efforts in the field of oxide research: heavy transition metal oxides with strong spin-orbit coupling, surfaces and interfaces of complex oxides, and using strain as a knob to tune electronic properties. I will also discuss our theoretical efforts -- ranging from the study of model Hamiltonians to low energy effective theories to ongoing collaborative efforts with experimentalists -- which are aimed at understanding the rich physics of these materials.
"Searching for the ttH(Hbb) and ttbb signal with novel techniques at CMS"
Marco Harrendorf , KIT
[Host: Chris Neu]
In the last ten years we have experienced the start and the first triumphs of the Large Hadron Collider (LHC) located at CERN in Geneva, Switzerland. Surely, the discovery of a Standard Model-like Higgs boson in 2012 stands out within this context. But even though, that further major findings like Physics beyond the Standard Model eluded us so far, the quest for understanding our elementary nature is ongoing under full steam. One of the outstanding important checks is the determination if the Higgs boson is really the Higgs boson predicted by the Standard Model. An important puzzle piece in this aspect will be the discovery of the ttH signal process providing us with a direct measurement of the Top-Higgs-Yukawa coupling. The search for ttH in the bbar decay channel benefits from the large branching fraction of 58% for the Higgs to bbar decay. At the same time, the large irreducible tt+bb background poses a major challenge and requires the use of advanced analysis techniques. A further crucial ingredient is the estimation and modelling of the tt+bb background via MC event generators which is still afflicted with large theoretical uncertainties.
This talk will discuss the work on the upcoming ttH(Hbb) analysis covering the 2016 LHC data set and ongoing work to reduce the uncertainties related to the tt+bb background. Furthermore, the talk will deliver a glimpse in the future of experimental particle physics by interspersing examples of novel techniques used in the analysis, e.g. the application of Neural Networks as a classifier, Continuous integration as an improvement of the analysis workflow, and NLO event generation for obtaining more accurate simulation data.
Wednesday, March 29, 2017
3:30 PM
Physics Building, Room 204
"The status of Supersymmetric Dark Matter after LHC Run I and alternatives from Grand Unification"
Keith Olive , University of Minnesota
[Host: Peter Arnold]
Wednesday, March 22, 2017
3:30 PM
Physics Building, Room 204
"Status and prospective of the SoLid/CHANDLER experiment"
Camillo Mariani , Virginia Tech
[Host: Donal Day]
The SoLid/CHANDLER experiment aims to make a measurement of very short baseline neutrino oscillations using reactor anti-neutrinos. For this purpose, a highly segmented detector was build out of PVT cubes lined with a 6LiF:ZnS(Ag)layer. Unlike neutrino experiments conducted deep underground, neutrino detectors used in a reactor environment need to operate in high levels of background radiation with very low shielding. Therefore, a reliable distinction between the neutrons produced in inverse beta decay events and signals caused by other background interaction is crucial. The composite of scintillation materials with different time constants enables the efficient use of pulse-shape analysis to discriminate against electromagnetic signals. In this talk I will present the SoLid detector, the signal identification with few example of inverse beta decays events that were collected during the first data taking of the first SoLid module and the future program that involves the use of the CHANDLER technology to increase the energy resolution of the SoLid detector.
[Host: Peter Arnold]
[Host: Peter Arnold]
[Host: Peter Arnold]
[Host: ]
[Host: Peter Arnold]
[Host: Peter Arnold]
"Searches for New Physics Through Third Generation Particles at the ATLAS Detector "
Allison McCarn , University of Michigan
[Host: Chris Neu]
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.
Wednesday, November 16, 2016
3:30 PM
Physics Building, Room 204
"New Physics Searches using Jet Substructure with the CMS Experiment"
Justin Pilot , UC-Davis
[Host: Chris Neu]
Many searches for new physics at the LHC involve decays to heavy objects such as W, Z, and Higgs bosons, or top quarks. I will present the latest algorithms to identify hadronic decays of these objects at high momentum, where decay products may overlap in the detector. These jet substructure algorithms aim to efficiently identify distinct topologies of particles within a jet, while simultaneously rejecting the large QCD backgrounds. I will show the latest results from CMS searches for new physics using these signatures, including searches for top quark pair resonances and vector-like top and bottom partner quarks. Looking toward the future, I will also discuss some new developments in the field of jet substructure being considered for new analyses.
Wednesday, November 9, 2016
3:30 PM
Physics Building, Room 204
"CERN LHC hi-lumi upgrades and Prospects for a 'Future Hadron Collider'"
Bruce P. Strauss , U.S. Department of Energy
[Host: Joe Poon]
The University of Virginia Advanced Research Computing Services (ARCS) group is committed to transforming computational research at UVA through consultation, education, and management of the University’s shared computing resources. We provide high-performance computing (HPC) expertise and service to UVA researchers from across disciplines. Our goals are to:
- Support the UVA research community's computational projects
- Advance HPC research at the University of Virginia and across the Commonwealth
- Provide computational training to a new generation of researchers
- Devise creative programming solutions on behalf of clients
- Foster a multi-disciplinary ethos
Wednesday, October 5, 2016
3:30 PM
Physics Building, Room 204
"Nonextremal black holes, subtracted geometry and holography"
Mirjam Cvetic , University of Pennsylvania
[Host: Diana Vaman]
We review the thermodynamic properties of general asymptotically flat black holes in four dimensions, suggestive of a dual conformal field theory interpretation. We introduce the so-called subtracted geometry as an ``asymptotically conical box'' of non-extremal black holes where the conformal symmetry becomes manifest. Employing holographic renormalization techniques in a variational problem in terms of equivalence classes of boundary data under the local asymptotic symmetries of the theory, we derive the conserved charges and the first law of thermodynamics for the subtracted geometry. We also formulate a holographic dictionary for this geometry in terms of a two-dimensional Einstein-Maxwell-Dilaton model.
"Photon-photon Interaction in Rydberg Atomic Ensemble"
Bing He , University of Arkansas
[Host: Olivier Pfister and Israel Klich]
The understanding of dynamical evolutions of interacting photon pulses in Rydberg atomic ensemble is the prerequisite for realizing quantum devices with such system. We present an approach that efficiently simulates the dynamical processes, using a set of local functions we construct to reflect the profiles of narrowband pulses. For two counter-propagating photon pulses, our approach predicts the distinct phenomena from the widely concerned Rydberg blockade to the previously less noticed significant absorption in the anomalous dispersion regime, which can occur by respectively setting the pulse frequency to the appropriate values. Our numerical simulations also demonstrate how spatially extending photon pulses become deformed under realistic non-uniform interaction over their distributions.
Wednesday, April 27, 2016
3:30 PM
Physics Building, Room 204
In LHC run1, the discovery of Higgs boson are striking success for the Standard Model (SM) again. Although it’s the most well-tested description of modern particle physics available today, SM is powerless in explaining hierarchy problem, dark matter in the observed universe, etc. Beyond-SM theories arise to rescue and one such theory that provides elegant solutions to many outstanding problems in SM is Supersymmetry. Based on LHC-the most powerful collider in the world, CMS experiment has achieved the chance to dig into the new particle production. This presentation will focus on one search of the susy evidence at cms, the analysis topic relies on the top pair +photons and met final state in the natural GMSB model. Currently, LHC is under the run2 data taking period at 13TeV, Run1 results and Run2 progress will be discussed.
Wednesday, April 20, 2016
3:30 PM
Physics Building, Room 204
"Constraining the Standard Model with Rare Electroweak Processes: Wgg and Zgg in CMS 8TeV Data"
Alberto Belloni , University of Maryland
[Host: Bob Hirosky]
Wednesday, April 13, 2016
3:30 PM
Physics Building, Room 204
"Measuring the top-Higgs coupling at CMS "
Evan Wolfe , UVA - Department of Physics
[Host: Chris Neu]
The top-Higgs coupling is one of the remaining characteristics that has yet to be measured for the newly discovered boson. Though the standard model predicts a value for this coupling, many extensions to the standard model provide enhancements to the predicted value. While indirect measurements of the top-Higgs coupling are possible, the best approach is measuring this coupling directly at the LHC -- and the best production mechanism is through the Higgs produced in association with a top-quark pair, ttH production. This presentation will discuss the ttH results from Run I at CMS, challenges and progress of the search in Run II, and future outlook for the top-Higgs coupling measurement.
Wednesday, March 30, 2016
3:30 PM
Physics Building, Room 204
"On neutrino masses and phenomenological implications: μ → e γ and μ → e conversion"
Trinh Le , UVA- Department of Physics
We present a model of neutrino masses in the framework of the Electroweak scale Right-handed neutrinos (EW-νR) model, which is constructed with a horizontal A4 symmetry. Such a model has several interesting phenomenological implications. We not only obtain the experimentally desired form of the PMNS matrix but also provide an explanation of why UPMNS is very different from VCKM. Moreover, the one-loop induced lepton flavor violating radiative decays li → lj γ and μ → e conversion in an extended mirror model might be related to each other under a good approximation that we have established. Implications concerning the possible detection of mirror leptons at the LHC and the ILC as well as future searches for μ → e conversion at Fermilab and J-PARC COMET are also discussed.
"Flavor Changing Leptonic Decays of Heavy Higgs Bosons"
Marc Sher , William & Mary
[Host: Chris Neu]
CMS has reported indications (2.4\sigma) of the decay of the Higgs boson into \mu\tau. The simplest explanation for such a decay would be a general Two Higgs Doublet Model (2HDM). In this case, one would expect the heavy neutral Higgs bosons, H and A, to also decay in a similar manner. We study two specific models. The first is the type III 2HDM, and the second is a 2HDM, originally proposed by Branco et al., in which all flavor-changing neutral processes are given by the weak mixing matrix. In the latter model, since mixing between the second and third generations in the lepton sector is large, flavor-changing interactions are large. In this model it is found that the decays of H and A to \mu\tau can be as high as 60 percent. This work has nothing to do with the 750 GeV diphoton resonance.
Wednesday, March 2, 2016
3:30 PM
Physics Building, Room 204
I will review the history of underlying event (UE) studies in hadron-hadron collisions starting with the first CDF UE analysis in 2000. Early CDF UE measurements at 1.8 TeV and 1.96 TeV; the CDF "Tevatron Energy Scan" UE results at 300 GeV, 900 GeV, and 1.96 TeV; LHC UE studies at 900 GeV and 7 TeV: and the recent LHC UE results at 13 TeV will be examined. I will discuss what we have learned from these studies beginning with the first CDF QCD Monte-Carlo model UE tune (Tune A), and ending with the latest CMS UE tunes (CUETP8S1, CUETP8M1, and CUETHS1).
Wednesday, January 27, 2016
3:30 PM
Physics Building, Room 204
Almost 30 years ago, the European Muon Collaboration uncovered a crisis in nuclear physics: part of the proton's spin was missing. The measured spin of the three valence quarks could not account for the known spin of the proton, and even today, we do not fully understand the proton's "spin budget." This "proton spin puzzle" has driven a revolution in our understanding of the complex structure of the proton as we search for the missing angular momentum.
One possible source of angular momentum is the polarization of radiated quarks and gluons which carry a very small percentage of the proton's energy (small x) and can only be measured at particle accelerators with very high energies. At high enough energies, multiple bremsstrahlung builds up a cascade of these small-x particles which may contain a substantial portion of the missing proton spin.
In this talk, I will describe the structure of this quantum evolution process for polarized quarks at small x. In contrast to the more familiar cascade of unpolarized particles at small x, the polarized evolution generates double logarithms of energy and grows more quickly at high energies. Its structure is much more complex than the unpolarized case, but early hints seem to suggest that the polarization may indeed become large at small x, making them an essential missing contribution to the proton spin puzzle.
Wednesday, December 2, 2015
3:30 PM
Physics Building, Room 204
"Searching for Astrophysical Neutrinos with Super Kamiokande"
Erin O'Sullivan , Duke University
[Host: Craig Group]
Reserved for Chemistry 3:30 - 5:30pm
Wednesday, November 11, 2015
3:30 PM
Physics Building, Room 204
"The MINERvA neutrino experiment at Fermilab"
Jeff Nelson , College of William and Mary
[Host: Craig Group]
"Supernova Neutrinos"
Jim Kneller , North Carolina State University
[Host: Craig Group and Bob Hirosky]
Studying the neutrino with experiments here on Earth is a slow business. This fundamental particle is just so ephemeral under terrestrial conditions that experimenters must push the boundaries of detector technology and their patience in order to measure its properties. In contrast, a core-collapse supernovae pushes Nature's boundaries of temperature and density to the point where neutrinos become strongly coupled components of the system. In such an environment it has been shown a laundry list of neutrino properties - both Standard Model and Beyond Standard Model - alters the dynamics of the explosion. Furthermore, the neutrino signal from the next supernova in our Galaxy will also allow us to observe to the heart the explosion and extract quantitative information we can use to compare to simulations. In this talk I present some of the contributions we at NC State have made in recent years to the understanding of the phenomenology of neutrinos in supernovae. I will pay particular attention to our recent demonstration that neutrino flavor transformation in a turbulent medium is similar to the interaction of light and matter and show how the recent generalization of the techniques we developed allow us to better understand the neutrino evolution with self-interaction as well as find uses well beyond neutrino astrophysics.
"String Theory and the Real World"
Jonathan Heckman , University of North Carolina at Chapel Hill
[Host: Bob Hirosky]
The Standard Model of particle physics provides a remarkably accurate description of Nature at small distance scales. But although this theory remains in close agreement with experiment, coupling the Standard Model to gravity leads to internal theoreticalinconsistencies at length scales much smaller than current experiments can probe. In this talk we review some of the recent progress made in formulating a self-consistent theory based on embedding the Standard Model in a strongly coupled phase of string theory known as "F-theory." We review how this construction leads to flavor physics models in both the quark and neutrino sectors. Time permitting, we also review recent efforts to make further contact with current and future experiments.
Wednesday, September 9, 2015
3:30 PM
Physics Building, Room 204
"Status and plans of dark matter searches with LUX and LZ "
Carter Hall , University of Maryland
[Host: Craig Group]
Wednesday, May 6, 2015
3:30 PM
Physics Building, Room 204
"BSM Tensor Interaction and Hadron Phenomenology"
Simonetta Liuti , University of Virginia
[Host: Donal Day]
"LPM Effect in Sequential Bremsstrahlung"
Shahin Iqbal , University of Virginia
[Host: Peter Arnold]
Tuesday, April 21, 2015
3:30 PM
Physics Building, Room 204
MeV neutrinos open new strategies and challenges for a variety of topics in astroparticle physics. I will first discuss their role in understanding core-collapse supernova physics. These supernovae are among the most energetic phenomena in the Universe yet their mechanism remains unresolved. I will outline the search for the next supernova neutrinos, and describe what supernova physics can be learned from their detections. Along the way, I will demonstrate the strong interplay between supernova physics and astronomy. I will then discuss the role of neutrinos in probing the particle nature of dark matter. Dominating the matter budget of the Universe, dark matter remains one of the foremost challenges in astroparticle physics and cosmology. Neutrinos are well-positioned to becoming a new window in which to study the Universe, bringing new insights, and potentially surprises.
"Search for disappearing tracks in proton-proton collisions at sqrt(s) = 8 TeV"
Jessica Brinson , The Ohio State University
[Host: Chris Neu]
Many experimental searches for supersymmetry, a proposed extension to the Standard Model, have been performed at the Large Hadron Collider. Since no evidence of supersymmetry has been found, the energy scales of the theory continue to be pushed higher and higher. However, if some supersymmetric particles are long-lived they may have been missed by other conventional searches. In this talk, I will present the results of a search for long-lived supersymmetric charged particles that decay within the CMS detector and produce the experimental signature of a 'disappearing track.'
"Entanglement Hamiltonians and the First Law for Entanglement Entropy"
Gabriel Wong , University of Virginia
[Host: Israel Klich & Diana Vaman]
In the first part of this talk we will present a path integral derivation of a general relation between the ground state entanglement Hamiltonian and the physical stress tensor for a Conformal Field Theory (CFT). For spherical entangling surfaces in a CFT, this leads to first law-like relation between variations of entanglement entropy (EE) and energy as well as a set of constraint equations for the EE variation.
Via AdS/CFT, these equations can be recast as Perturbative Einstein's Equations in the bulk dual.
In the second part, we will present results on the entanglement Hamiltonian (EH) of chiral fermions living on a spatial circle. In particular we focus on the effects of periodic vs. anti periodic boundary conditions on the EH. We will relate the calculation of the fermion EH to the solution of a Riemann Hilbert Problem, and propose a generalization of Riemann Hilbert Problem for spinor bundles in higher dimensions.
Wednesday, March 25, 2015
3:30 PM
Physics Building, Room 204
"An algorithmic approach to string compactification"
Lara Anderson , Virginia Tech
[Host: Peter Arnold]
In this talk, I will outline recent progress in constructing heterotic string compactifications with realistic particle spectra and couplings in their low energy effective theories. This will involve an exploration of string "compactification" -- the process of describing very small extra spatial dimensions and how their shape and properties could effect observable physics. I will discuss new results on two long-standing challenges in string constructions. The first is a large scale, algorithmic approach to geometrically realizing the Standard Model of particle physics in string theory. The second is a presentation of new tools to address the problem of moduli stabilization (i.e the removal of unphysical massless particles from arising in the low energy physics of a string solution).
Thursday, March 19, 2015
3:30 PM
Physics Building, Room 204
"Observing Ultra-High Energy Cosmic Rays with Smartphones"
Chase Shimmin , University of California, Irvine
[Host: Chris Neu]
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, February 17, 2015
3:30 PM
Physics Building, Room 204
MeV neutrinos open new strategies and challenges for a variety of topics in astroparticle physics. I will first discuss their role in understanding core-collapse supernova physics. These supernovae are among the most energetic phenomena in the Universe yet their mechanism remains unresolved. I will outline the search for the next supernova neutrinos, and describe what supernova physics can be learned from their detections. Along the way, I will demonstrate the strong interplay between supernova physics and astronomy. I will then discuss the role of neutrinos in probing the particle nature of dark matter. Dominating the matter budget of the Universe, dark matter remains one of the foremost challenges in astroparticle physics and cosmology. Neutrinos are well-positioned to becoming a new window in which to study the Universe, bringing new insights, and potentially surprises.
Wednesday, February 4, 2015
3:30 PM
Physics Building, Room 204
"Sterile neutrinos and neutrino interactions: to see or not to see, that is the question"
Mike Kordosky , College of William and Mary
[Host: Craig Group]
Wednesday, January 28, 2015
3:30 PM
Physics Building, Room 204
"Search for new physics in multijet final states with the CMS experiment"
Tutanon Sinthuprasith , Brown University
[Host: Chris Neu]
With the successful discovery of the standard model (SM) Higgs boson in 2012, the emphasis of the LHC physics program has shifted to understanding its properties and searching for new physics beyond the SM (BSM). Among other fascinating physics avenues at the LHC, the search for BSM physics has been the center of my interests.
The BSM physics may lie hidden in the extension of the strong sector or the uncover territory of R-parity Violating Supersymmetry (RPV SUSY). I will present the current searches for the BSM physics in multijet final states — 8 and 10 jets — predicted by three benchmark models — Coloron, Axigluon, and Gluino (RPV SUSY). The data sample, corresponding to an integrated luminosity of 19.7 fb^{-1} of proton-proton collisions at a center-of-mass energy of 8 TeV, was collected with the CMS experiment during 2012. I will further discuss about the techniques used in the multijet background estimation. What are the weaknesses and strengths of these methods and in which direction I am pursuing the BSM physics in multijet final states at the CMS experiment.
"Mass, width, and quantum numbers: everything about the Higgs boson with 20 events"
Andrei Gritsan , Johns Hopkins University
[Host: Craig Group]
The recently discovered Higgs boson is a completely new form of matter-energy and is believed to be a manifestation of the all-penetrating field responsible for generating mass of all elementary particles. It was observed as a resonance with mass near 125 GeV in the decay to a pair of two vector bosons on the ATLAS and CMS experiments at LHC in 2012. It is expected to have the width of about 4 MeV and the quantum numbers of the vacuum (J^PC=0^++). Yet experimental resolution allowed us to set an upper limit on the width of about 3400 MeV and only a limited number of spin-parity assignments were tested until recently. Two recent results from the CMS experiment provided a breakthrough in the study of the H boson properties: one is the measurement of the width from an interplay between the off-shell and on-shell production of the H boson, leading to a 22 MeV limit on the width, and the other is the tensor structure measurement of the H boson interactions with four pairs of vector bosons, leading to constraints on its spin-parity properties. Both results will be discussed.
Wednesday, November 19, 2014
3:30 PM
Physics Building, Room 204
"Search for Third-Generation Scalar Leptoquarks and R-Parity Violating Top Squarks"
Kevin Pedro , University of Maryland
[Host: Chris Neu]
A search for pair production of third-generation scalar leptoquarks and supersymmetric top quark partners, top squarks, in final states involving tau leptons and bottom quarks is presented. The search uses events from a data sample of proton-proton collisions corresponding to an integrated luminosity of 19.7 inverse femtobarns, collected with the CMS detector at the LHC with sqrt(s)=8 TeV. The number of observed events is found to be in agreement with the expected standard model background. Third-generation scalar leptoquarks with masses below 740 GeV are excluded at 95% confidence level, assuming a 100% branching fraction for the leptoquark decay to a tau lepton and a bottom quark. In addition, this mass limit applies directly to top squarks decaying via an R-parity violating coupling lambda'[333]. The search also considers a similar signature from top squarks undergoing a chargino-mediated decay involving the R-parity violating coupling lambda'[3jk]. Each top squark decays to a tau lepton, a bottom quark, and two light quarks. Top squarks in this model with masses below 580 GeV are excluded at 95% confidence level. The constraint on the leptoquark mass is the most stringent to date, and this is the first search for top squarks decaying via lambda'[3jk].
"Beyond the first law of entanglement"
Misha Smolkin , University of California, Berkeley
[Host: Israel Klich]
I will start with the first law of entanglement and its applications in QFT, then I will argue that certain calculations can be extended beyond the range of applicability of the first law and present a number of simple examples. The talk will culminate with a detailed analysis of certain open questions and related calculations.
Wednesday, November 5, 2014
3:30 PM
Physics Building, Room 204
Wednesday, October 29, 2014
3:30 PM
Physics Building, Room 204
"COHERENT Neutrino Physics at the Spallation Neutron Source"
Kate Scholberg , Duke University
[Host: Craig Group]
Wednesday, October 1, 2014
3:30 PM
Physics Building, Room 204
"Quest for the nature of the neutrino"
Reyco Henning , University of North Carolina
[Host: Craig Group]
Neutrinos are remarkable particles. They are the only known fermions that interact only via the weak force and have unusually small but finite masses. Although we have learned much about their nature over the past decades, fundamental question remain. A key one is whether neutrinos are Majorana fermions, which would imply that they are their own antiparticles. Surprisingly, this is a very difficult property to test experimentally, and the current best experimental method is to search for neutrinoless nuclear double-beta decay (NDBD). Just demonstrating the existence of this decay would show that neutrinos are Majorana fermions. In this talk I will give a theoretical and historical overview of NDBD, followed by a discussion of the experimental challenges and current international efforts to search for NDBD, with an emphasis on the Majorana experiment that is being led by UNC and Oak Ridge National Lab.
Tuesday, April 29, 2014
3:30 PM
Physics Building, Room 204
"Color-Kinematic Symmetry and Gauge-Gravity Connection in the Space of Generalized Propagating Matrix and in Light-Like gauges"
York-Peng Yao , University of Michigan
[Host: Diana Vaman]
Friday, April 18, 2014
3:30 PM
Physics Building, Room 203
"String Theory, Our Real World, and Higgs bosons"
Gordon Kane , University of Michigan
[Host: Dinko Pocanic]
Wednesday, April 16, 2014
3:30 PM
Physics Building, Room 204
Wednesday, April 9, 2014
3:30 PM
Physics Building, Room 204
"IceCube: Astrophysical neutrino measurements from the South Pole"
Mike DuVernois , Wisconsin IceCube Particle Astrophysics Center
[Host: PQ Hung]
"Is the size of Θ13 related to the smallness of the solar mass splitting?"
Amitava Raychaudhuri , Calcutta University
[Host: PQ Hung]
"Evidence for s-channel single top production at CDF"
Hao Liu , University of Virginia
[Host: Craig Group]
Wednesday, November 13, 2013
3:30 PM
Physics Building, Room 204
"First Dark Matter Search Results from the LUX Detector"
Karen Gibson , Case Western Reserve University
[Host: Chris Neu]
Wednesday, November 6, 2013
3:30 PM
Physics Building, Room 204
"Non-Constant Dark Energy Models and the Possible Fates of the Universe"
Kevin Ludwick , University of Virginia
[Host: PQ Hung]
Wednesday, October 30, 2013
3:30 PM
Physics Building, Room 204
"Neutrino Advances and Developments in Finite Group Models"
David Eby , Vanderbilt University
[Host: Kevin Ludwick]
Wednesday, October 23, 2013
3:30 PM
Physics Building, Room 204
Wednesday, October 16, 2013
3:30 PM
Physics Building, Room 204
"Recent results from the KLOE/KLOE-2 experiment"
Anthony Palladino , INFN Frascati, Italy
[Host: Dinko Pocanic]
Wednesday, October 2, 2013
3:30 PM
Physics Building, Room 204
"Improving Weak Boson Fusion (WBF) LHC Higgs analyses with Fox-Wolfram Moments"
Catherine Bernaciak , University of Heidelberg
[Host: Craig Group]
Wednesday, September 25, 2013
3:30 PM
Physics Building, Room 204
"The latest evidence for s-channel single top production"
Aran Garcia-Bellido , University of Rochester
[Host: Bob Hirosky]
Wednesday, September 18, 2013
3:30 PM
Physics Building, Room 204
Tuesday, September 17, 2013
3:30 PM
Physics Building, Room 204
"Polaroid jetography: an album of jet physics measurements and searches at the ATLAS experiment"
Caterina Doglioni , University of Geneva
[Host: Bob Hirosky]
Wednesday, August 28, 2013
3:30 PM
Physics Building, Room 204
"Long-baseline neutrino experiments with the NuMI beam"
Patricia Vahle , College of William and Mary
[Host: R. Craig Group]
"Seach for Standard Model Higgs in t‾tH, H→ b¯b decay channel at √ s = 8 TeV"
John Wood , University of Virginia
[Host: Chris Neu]
"Anomalies in the Forward-Backward Asymmetry of Top Quark Pair Production at the Tevatron"
Jon Wilson , University of Michigan
[Host: Craig Group]
"A Search for Gauge Mediated Supersymmetry Breaking at the Compact Muon Solenoid in Events with Two Photons, Third Generation Quarks, and Large Missing Energy"
Brian Francis , University of Virginia
[Host: Brad Cox]
Wednesday, March 27, 2013
12:00 PM
Physics Building, Room 313
Wednesday, March 20, 2013
3:30 PM
Physics Building, Room 204
"Search of Magnetic Monopoles with the NOvA Detector"
Zukai Wang , University of Virginia
[Host: Craig Dukes]
Wednesday, February 27, 2013
3:30 PM
Physics Building, Room 204
"Electroweak-scale Right-handed Neutrino Model and 126 GeV Higgs-like Particle"
Ajinkya Kamat , University of Virginia
[Host: PQ Hung]
"Electroweak-scale Right-handed Neutrino Model Contribution to Oblique Parameters"
Vinh Hoang , University of Virginia
[Host: PQ Hung]
"How to understand superfluids using field theory"
Mark Alford , Washington University in St. Louis
[Host: Diana Vaman]
I will show how one can translate between the macroscopic two-fluid model and a microscopic field theoretic description, using the simplest field theory that can show Bose-Einstein condensation, namely the complex scalar field.
Questions that will be answered include:
* How can one get two fluids from a single field? * What is the relationship between the different formalisms that have been proposed for relativistic superfluids? * What is the role of the Goldstone boson?
Wednesday, December 5, 2012
3:30 PM
Physics Building, Room 204
"Indirect Searches for Dark Matter with the Fermi Large Area Telescope"
Andrea Albert , Ohio State University
[Host: Chris Neu]
Thursday, November 15, 2012
2:30 PM
Physics Building, Room 313
"Continuity of the Deconfinement Transition in (Super) Yang Mills Theory"
Thomas Schaefer , North Carolina State University
[Host: Diana Vaman]
More technical abstract: We study the phase diagram of SU(2) Yang-Mills theory with one adjoint Weyl fermion on R^3xS^1 as a function of the fermion mass m and the compactification scale beta. This theory reduces to thermal pure gauge theory as m->infinity and to circle-compactified (twisted) susy gluodynamics in the limit m->0. In the m-L plane, there is a line of center symmetry changing phase transitions. In the limit m->infinity, this transition takes place at beta_c=1/T_c, where T_c is the critical temperature of the deconfinement transition in pure Yang-Mills theory. We show that near m=0, the critical scale beta_c can be computed using semi-classical methods and that the transition is of second order. This suggests that the deconfining phase transition in pure Yang-Mills theory is continuously connected to a phase transition that can be studied in weak coupling. The center symmetry changing phase transition arises from the competition of fractionally charged instanton-monopoles and instanton molecules. The calculation can be extended to higher rank gauge groups and non-zero theta angle.
"New technique(s) for mass measurement at hadron colliders"
Kaustubh Agashe , University of Maryland
[Host: Diana Vaman]
Wednesday, October 24, 2012
3:30 PM
Physics Building, Room 204
"Flavor Violation and theta(13) in the A4 Randall-Sundrum Model"
Avihai Kadosh , University of Groningen
[Host: Israel Klich]
In particular, I will demonstrate the way realistic CKM and PMNS matrices can be accommodated with natural O(1) parameters, considering also the recent measurements of theta(13) by RENO and DAYA Bay. I then discuss the phenomenology of RS-A4 and the most significant constraints coming from EWPM and rare processes in both the quark and lepton sectors. Special attention will be given to the calculation of 1-loop contributions to dipole operators relevant for the nEDM.
Finally, I discuss Tree level contributions to cLFV (mu-->e,3e) and B_{s,d}-->mu+mu- mediated by anomalous Z couplings, in light of the wealth of current day and future experiments addressing these processes. It is shown that cLFV together with EWPM, impose the strongest constraints on the Kaluza-Klein scale and the model parameters.
Wednesday, September 12, 2012
3:30 PM
Physics Building, Room 204
"Looking for Light at the End of the LHC Tunnel: The Search for SUSY with Photons at CMS"
David Mason , Fermi National Accelerator Laboratory
[Host: Brad Cox]
"Search for the Higgs at the LHC in the Channel H->WW->lvjj"
Joey Goodell , University of Virginia
[Host: Chris Neu]
"Explaining the Tevatron ttbar asymmetry with light axigluons"
Christian Spethmann , Boston University
[Host: PQ Hung]
"The Spin of Holographic Electrons at Nonzero Density and Temperature"
Chris Herzog , Princeton University
[Host: Diana Vaman]
"The Energy Dependence of the Underlying Event"
Rick Field , University of Florida
[Host: Craig Group]
Wednesday, April 4, 2012
3:30 PM
Physics Building, Room 204
"Measurement of CP Violation in Bs to J/Psi Phi Decays at CDF"
Gavril Giurgiu , Johns Hopkins University
[Host: Brad Cox]
Saturday, March 31, 2012
10:00 AM
Physics Building, Room 204
"Virginia and Maryland String and Particle Theory Meeting"
Balasubramanian, Cvetic, Kharzeev, & Langacker , University of Pennsylvania, Brookhaven National Laboratory, & Institute for Advanced Study
[Host: Diana Vaman]
"The chiral magnetic effect and chiral hydrodynamics of relativistic plasmas"
The interplay of quantum anomalies, topology and magnetic field results in a number of surprising phenomena in relativistic plasmas. In particular, the chirality imbalance induces the separation of electric charge along the axis of magnetic field (the Chiral Magnetic Effect, CME). The existence of CME has been confirmed by the lattice QCDxQED computations, and there is an evidence for it from heavy ion experiments at RHIC and LHC. The CME current is non-dissipative, and persists in strongly coupled systems that admit hydrodynamical description. Quantum anomalies significantly affect the hydrodynamics of relativistic plasmas leading in particular to the emergence of novel gapless collective excitations. Apart from the quark-gluon plasma, the CME current and related phenomena can exist in chiral materials (e.g. graphene, topological insulators, and Weyl semi-metals).
11 a.m.-12 p.m. - Mirjam Cvetic (University of Pennsylvania)
"General Black Holes and Their Microscopics"
We review properties of multi-charged rotating black holes in asymptotically Minkowski and anti-deSitter space-times, as solutions of maximally supersymmetric compactifications of String Theory. We focus on recent progress in deriving the conformal invariance and the microscopics of general, asymptotically flat rotating black holes in four- and five-dimensions.
2-3 p.m. - Vijay Balasubramanian (University of Pennsylvania)
"Momentum space entanglement and renormalization in quantum field theory"
The degrees of freedom of any interacting quantum field theory are entangled in momentum space. Thus, in the vacuum state, the infrared degrees of freedom are described by a density matrix with an entanglement entropy. We derive a relation between this density matrix and a Wilsonian effective action. We argue that the entanglement entropy of and mutual information between subsets of field theoretic degrees of freedom at different momentum scales are natural observables in quantum field theory and demonstrate how to compute these in perturbation theory. The results may be understood heuristically based on the scale-dependence of the coupling strength and number of degrees of freedom. We measure the rate at which entanglement between degrees of freedom declines as their scales separate and suggest that this decay is related to the property of decoupling in quantum field theory.
3-4 p.m. - Paul Langacker (Institute for Advanced Study)
"New Physics from the String Vacuum"
Concrete semi-realistic string constructions often lead to predictions for low energy physics that
are more complicated than the usual MSSM paradigm. These often include string remnants such as additional U(1)' gauge symmetries, extended quasi-chiral fermion sectors, and extended Higgs/neutralino sectors.
Non-standard mechanisms for obtaining small Dirac or Majorana neutrino masses (or both) are another common occurence. Examples of such ``beyond the MSSM'' physics and their consequences will be discussed, mainly drawn from Type IIA quivers.
"The New Muon g-2 Experiment at Fermilab"
Mandy Rominsky , Fermi National Accelerator Laboratory
[Host: Bob Hirosky]
"T-odd Transverse Momentum Distributions and Role of the Strong Coupling Constant"
Aurore Courtoy , IFPA University of Liege
[Host: Simonetta Liuti]
"Is the universe as we know it unstable?: What a Higgs mass ~ 125 GeV would mean for the Minimal Standard Model"
Peter Arnold , University of Virginia
[Host: Craig Dukes]
Wednesday, January 25, 2012
3:30 PM
Physics Building, Room 204
"Hydrodynamic Noise and Bjorken Expansion"
Mikhail Stephanov , University of Illinois at Chicago
[Host: Peter Arnold]
"Measurement of the Triple Differential Cross Section of Photon plus Jet in pp Collisions at 7 TeV"
Chuanzhe Lin , University of Virginia
[Host: Bob Hirosky]
Wednesday, November 16, 2011
3:30 PM
Physics Building, Room 204
Wednesday, November 2, 2011
3:30 PM
Physics Building, Room 204
"Radio Detection of High Energy Cosmic Ray Showers"
Abaz Kryemadhi , Messiah College
[Host: Bob Hirosky]
Wednesday, October 12, 2011
3:30 PM
Physics Building, Room 204
"Consistent truncations of IIB on Sasaki-Einstein manifolds and N=2 supergravity in five dimensions"
Phillip Szepietowski , UVA
[Host: Diana Vaman]
Wednesday, October 5, 2011
3:30 PM
Physics Building, Room 204
"Measurement of the Differential Cross Section for Isolated Prompt Photon Production in pp Collisions at 7 TeV"
Ted Kolberg , Notre Dame
[Host: Chris Neu]
"Search for the SM Higgs Boson in Lepton plus Jets Final States"
Huong Nguyen , University of Virginia
[Host: Bob Hirosky]
Wednesday, April 20, 2011
3:30 PM
Physics Building, Room 204
Wednesday, April 13, 2011
3:30 PM
Physics Building, Room 204
"The Upsilon and the SiPM: a particle from the past and its place in current LHC physics, and a new photo sensor and its possible future in detectors."
Jake Anderson , Fermilab
[Host: Brad Cox]
Tuesday, April 12, 2011
3:30 PM
Physics Building, Room 204
"A search for resonant production of Top quarks pairs at CDF"
Yuri Oksuzian , UVa
[Host: Craig Group]
Wednesday, March 30, 2011
3:30 PM
Physics Building, Room 204
"Understanding the Quark Gluon Plasma"
Christine Nattrass , University of Tennessee, Knoxville
[Host: Peter Arnold]
Wednesday, February 23, 2011
3:30 PM
Physics Building, Room 204
"Topological Insulators, Gravity and Torsion"
Rob Leigh , University of Illinois
[Host: Diana Vaman ]
Wednesday, February 9, 2011
3:30 PM
Physics Building, Room 204
"Fluctuation, dissipation, and thermalization in non-equilibrium AdS5 black hole geometries"
Derek Teaney , SUNY at Stony Brook
[Host: Peter Arnold]
Wednesday, February 2, 2011
3:30 PM
Physics Building, Room 204
"Fermion Bag Approach to Lattice Field Theories"
Shailesh Chandrasekharan , Duke University
[Host: Peter Arnold]
"Setting up jet-modification as a probe of QCD media at HERA, RHIC and LHC"
Abhijit Majumder , Ohio State
[Host: Peter Arnold]
Wednesday, January 19, 2011
3:30 PM
Physics Building, Room 204
Wednesday, December 1, 2010
3:30 PM
Physics Building, Room 204
"Jet energy loss and stopping distances in weakly-coupled quark-gluon plasma"
Wei Xiao , University of Virginia
[Host: Peter Arnold]
Wednesday, November 17, 2010
3:30 PM
Physics Building, Room 204
Wednesday, November 10, 2010
3:30 PM
Physics Building, Room 204
"Dynamical Electroweak Symmetry Breaking in the Standard Model with a Heavy Fourth Generation"
Chi Xiong , University of Virginia
[Host: Peter Arnold]
"Low-Mass Dimuons at CDF: Dark Forces, Higgs Bosons, and Data Anomalies"
Chris Hays , Oxford University
[Host: Chris Neu]
Wednesday, April 28, 2010
3:30 PM
Physics Building, Room 204
"Searching for Gauge-Mediated Supersymmetry Breaking in the Large Hadron Collider's First Events"
Rachel Yohay , University of Virginia
[Host: Brad Cox]
Wednesday, April 14, 2010
3:30 PM
Physics Building, Room 204
"Spear-fishing at the LHC -- Using Weak Bosons to Understand Proton Structure at High Energy"
Jeremy Mans , University of Minnesota
[Host: Bob Hirosky]
Monday, April 12, 2010
3:30 PM
Physics Building, Room 204
Wednesday, March 31, 2010
3:30 PM
Physics Building, Room 204
"Search for Lepton Flavor Violating decay Bs (Ks μ ± e ∓ )"
Emmanuel Munyangabe , University of Virginia
[Host: Craig Dukes]
Wednesday, March 24, 2010
3:30 PM
Physics Building, Room 204
"Search for WZ in the l nu b bbar Final State at CDF"
Justin Keung , University of Pennsylvania
[Host: Chris Neu]
Wednesday, March 17, 2010
3:30 PM
Physics Building, Room 204
Wednesday, January 20, 2010
3:30 PM
Physics Building, Room 204
"Introduction to AdS/CFT and its applications"
Eddy Barnes , University of Virginia
[Host: Diana Vaman]
Wednesday, December 2, 2009
3:30 PM
Physics Building, Room 204
"Collider and Flavor Phenomenology in the Scalar sector of Warped Extra Dimensions"
Manuel Toharia , University of Maryland
[Host: Diana Vaman]
Wednesday, November 18, 2009
3:30 PM
Physics Building, Room 204
Wednesday, November 4, 2009
3:30 PM
Physics Building, Room 204
"Flavor-branes in gauge/string duality and M-theory"
Johannes Schmude , Swansea University
[Host: Diana Vaman]
Tuesday, October 27, 2009
3:30 PM
Physics Building, Room 204
"Reorganizing the QCD pressure at intermediate coupling"
Michael Strickland , Gettysburg College
[Host: Peter Arnold ]
Wednesday, October 21, 2009
3:30 PM
Physics Building, Room 204
"Development of a Digital Hadron Calorimeter"
Jose Repond , Argonne National Laboratory
[Host: Craig Dukes]
Wednesday, October 14, 2009
3:30 PM
Physics Building, Room 204
"Studies of D -> pi e nu and D -> K e nu at CLEO-c"
Laura Fields , Cornell University
[Host: Craig Dukes]
Wednesday, October 7, 2009
3:30 PM
Physics Building, Room 204
"Search for electron antineutrinos from the Sun with KamLAND detector"
Oleg Perevozchikov , University of Tennessee
[Host: Craig Dukes]
Wednesday, September 23, 2009
3:30 PM
Physics Building, Room 204
"Commissioning and Status of the ATLAS pixel detector at the LHC"
Eugene Galyaev , CERN
[Host: Craig Dukes]
"The Search for Neutralino Dark Matter with the AMANDA Neutrino Telescope"
Ralf Ehrlich , University of Maryland
[Host: Craig Dukes]
"H->WW*->mu+nu+j+j : A Single Channel's Search for the Higgs at the Tevatron"
Shannon Zelitch , University of Virginia
[Host: Bob Hirosky]
"Observation of the rare charmed B decay, Bd to D*+ a0-, at the BaBar experiment: On finding a needle in a haystack."
Hella Snoek , University of Amsterdam/NIKHEF - BaBar
[Host: Chris Neu]
"Recent results of the photon plus heavy flavor jet cross sections at D0"
Daniel Duggan , Florida State University - D0
[Host: Chris Neu]
"Measurement of the Inclusive Isolated Prompt Photon Cross Section at CDF"
Carolina Deluca , IFAE - CDF
[Host: Chris Neu]
Wednesday, February 18, 2009
3:30 PM
HEP Building, Room 123
"Beauty in photoproduction at HERA"
Sarah Boutle , University College London, ZEUS
[Host: Chris Neu]
Wednesday, February 11, 2009
3:30 PM
HEP Building, Room 123
Monday, February 2, 2009
3:30 PM
Physics Building, Room 204
"CP Violation for the Heaven and the Earth - - - Sighting the 4th Generation?"
W.S. Hou , National Taiwan University
[Host: PQ Hung]
Wednesday, January 28, 2009
3:30 PM
Physics Building, Room HEP 123
"LAr calorimeter commissioning and search for a light stop"
Zhayou Yang , Carleton University
[Host: Chris Neu]
Wednesday, December 3, 2008
3:30 PM
Physics Building, Room 204
"Standard Model Higgs Searches with D0 in RunII"
Michael Kirby , Northwestern University
[Host: Chris Neu]
Wednesday, November 12, 2008
3:30 PM
Physics Building, Room 204
"Search for Higgs Bosons Produced in Association with W Bosons at CDF"
Jason Slaunwhite , Ohio State University
[Host: Chris Neu]
Wednesday, October 22, 2008
3:30 PM
Physics Building, Room 204
"Study of Charmless Inclusive Semileptonic B Decays and Measurement of the CKM Matrix Element |Vub| with the BaBar Detector"
Virginia Azzolini , IFIC-University of Valencia
[Host: Chris Neu]
"Search for new physics with b-quark jets"
Viktor Veszpremi , Cornell University
[Host: Christopher Neu]
"Measuring Fully Leptonic Charged B Decays in the Recoil of Semileptonic B Decays at BaBar"
Luke Corwin , Ohio State University
[Host: Chris Neu]
"The CLEAR Experiment: Measuring Neutrino-Nucleus Coherent Scattering at the Spallation Neutron Source"
Kate Scholberg , Duke University
[Host: Craig Dukes]
Wednesday, September 3, 2008
3:30 PM
Physics Building, Room 204
"Search for the Standard Model Higgs Boson at CDF Run II"
Brandon Parks , Ohio State University
[Host: Chris Neu]
"Leptogenesis in a model of dark energy and dark matter"
Huicheng Guo , University of Virginia
[Host: Bob Hirosky]
Wednesday, April 2, 2008
3:30 PM
Physics Building, Room 204
"Search for Evidence of Neutralinos at the LHC"
Michael Balazs , University of Virginia
[Host: Bob Hirosky]
Wednesday, March 19, 2008
3:30 PM
Physics Building, Room 204
Wednesday, February 6, 2008
3:30 PM
Physics Building, Room 204
"How Statistics Just Might Improve Your Experiment"
Jim Linnemann , Michigan State University
[Host: Bob Hirosky]
"Signals for Composite Higgs models in top/W/Z physics"
Kaustubh Agashe , University of Maryland
[Host: Bob Hirosky]
"Results on mixing, Δ Γ s and related CP violation in B s meson system at Tevatron"
Dmitri Tsybychev , Stony Brook
[Host: Bob Hirosky]
Wednesday, October 3, 2007
3:30 PM
Physics Building, Room 204
Wednesday, May 2, 2007
3:30 PM
Physics Building, Room 204
"The search for K L 0 -> π 0 π 0 μ + μ - and K L L -> π 0 μ + μ - "
David Phillips , University of Virginia
[Host: E. Craig Dukes]
Wednesday, April 18, 2007
3:30 PM
Physics Building, Room 204
Wednesday, April 4, 2007
3:30 PM
Physics Building, Room 204
"Hamiltonian approach to Yang-Mills theories in 2+1 dimensions: glueball and meson mass spectra"
Alexandr Yelnikov , Virginia Tech
[Host: Peter Arnold]
Wednesday, March 28, 2007
3:45 PM
Physics Building, Room 204
Wednesday, February 28, 2007
3:30 PM
Physics Building, Room 204
"Polarization Transfer in 4He(e,e'p): Is the Ratio G_Ep/G_Mp Modified in the Nuclear Medium?"
Steffen Strauch , University of South Carolina
[Host: Simonetta Liuti]
"CLEO-c: A New Frontier of Weak and Strong Interactions"
Daniel Cronin-Hennessy , University of Minnesota
[Host: E. Craig Dukes]
"Bulk Viscosity of High Temperature QCD"
Caglar Dogan , University of Virginia
[Host: E. Craig Dukes]
Wednesday, January 24, 2007
3:30 PM
Physics Building, Room 204
"Recent QCD Measurements at D-Zero"
Duncan Brown , University of Texas, Arlington
[Host: Bob Hirosky]
"Worldline Instantons and Pair Production"
Qinghai Wang , Unversity of Connecticut
[Host: Paul Fendley]
"Hadronic Particle Production and the Future of Neutrino Physics"
Andrew J. Norman , University of Virginia
[Host: E. Craig Dukes]
"Hairpin Diagrams and the Planar Equivalence of One-Flavor QCD and N=1 Supersymmetric Yang-Mills Theory"
Patrick Keith-Hynes , UVA
[Host: Hank Thacker]
Wednesday, March 15, 2006
3:30 PM
Physics Building, Room 204
"Accurate Lattice Calculations for Quark Flavor Physics"
Matthew Wingate , University of Washington
[Host: Hank Thacker]
Wednesday, February 1, 2006
3:30 PM
Physics Building, Room 204
Wednesday, January 18, 2006
3:30 PM
Physics Building, Room 204
"Chiral Effective-Field Theory in the Resonance Region"
Vladimir Pascalutsa , The College of William and Mary /Jefferson Lab - Theory Group
[Host: Cole Smith]
Wednesday, November 16, 2005
3:30 PM
Physics Building, Room 204
"208Pb Radius Experiment -- PREX"
Robert Michaels , Thomas Jefferson National Accelerator Facility, USA
[Host: Donal Day]
Thursday, April 14, 2005
2:30 PM
Physics Building, Room 313
"Neutrino Oscillations and the MINOS Experiment"
Nathanial Tagg , Oxford University
[Host: Craig Dukes]
"Searching for Neutrino Oscillations: Early Results from MiniBooNE"
Bill Louis , LANL
[Host: P.Q. Hung]
"Leptogenesis with Massive Neutrinos Abstract"
E. Paschos , University of Dortmund, Germany
[Host: Brad Cox]
Wednesday, January 26, 2005
3:30 PM
Physics Building, Room 204
"Status of Nuclear Physics and High Energy Research in Vietnam"
Vo Van Thuan , Institute for Nuclear Science and Technology, Hanoi
[Host: P. Q. Hung]
Wednesday, December 8, 2004
3:30 PM
Physics Building, Room 204
"3D Parton Imaging of the Nucleon in High Energy pp and pA Collisions"
Christian Weiss , Jefferson Laboratory
[Host: Simonetta Liuti]
"Recent Results From KLOE at DAFNE"
Matteo Palutan , Laboratori Nazionali di Frascati
[Host: Sergio Conetti]
"The Decay Σ+ → pµ+µ- and Possible New Physics from HyperCP"
HyangKyu Park , University of Michigan
[Host: Hank Thacker]
"Gross-Witten Point and Deconfinement in Matrix Models"
Rob Pisarski , Brookhaven National Lab
[Host: Hank Thacker]
"A High Statistics Search for the Theta-plus Pentaquark"
Mike Longo , University of Michigan
[Host: Craig Dukes]
"A Neural Network Analysis of the Top Cross Section at CDF"
Radu Marginean , Ohio State
[Host: Bob Hirosky]
"Lambda_c and Lambda_b Measurements From FOCUS and D0"
Abaz Kryemadhi , University of Indiana
[Host: Bob Hirosky]
"Some Old Puzzles of Particle Physics and Cosmology in the Light of the the Two Measures Theory"
Alexander Kaganovich , Ben Gurion University
[Host: P.Q. Hung]
"The MECO Experiment to Search for Mu N- ---> e- N with 10-17 Sensitivity"
Bill Molzon's , University of California at Irvine
[Host: Craig Dukes]
"Effective Interactions are Effective Interactions"
Barry Holstein , University of Massachusetts
[Host: Hank Thacker]
"To the Frontiers of HighField/High Energy Density Physics and Ultrafast Processes via Energy Recovering Linacs"
Swapan Chattopadhyah , JLab
[Host: Blaine Norum]
"Search For New Direct CP Violation in Neutral Kaon Decays"
Michael Ronquest , UVA
[Host: Hank Thacker]
"Collective Modes of an Anisotropic QGP"
Mike Strickland , Techische Universitat , Vienna
[Host: Peter Arnold]
"Precision Measurement of the Weak Mixing Angle in Parity-Violating Moller Scattering"
Imran Younus , Syracuse University
[Host: Craig Dukes]
"Measurement of the Branching Fraction for K-long -> mu+ mu- e+ e-"
Andrew Norman , College of William and Mary
[Host: Craig Dukes]
Monday, August 18, 2003
3:00 PM
Physics Building, Room 313
Wednesday, May 7, 2003
4:00 PM
Physics Building, Room 313
"FINeSE: Fermilab Intense Neutrino Scattering Experiment"
Dr. Bonnie Fleming , FermiLab
[Host: Lanchun Lu]
Wednesday, April 16, 2003
3:00 PM
Physics Building, Room 204
"Viewing the nucleon through "color" filters"
Prof. Xiangdong Ji , Univ. of Maryland
[Host: Xiaotong Song]
"Photon emission from dense quark matter in compact stars"
Carston Vogt , Nordita
[Host: J. Lenaghan]
"Transport coefficients in hot field theory"
Gert Aarts , Ohio State University
[Host: Peter Arnold]
Wednesday, February 19, 2003
3:30 PM
Physics Building, Room 204
"Panning for Gold (or Finding your physics in a torrent of data)"
Prof. Robert Hirosky , UVA
[Host: Brad Cox]
"Holographic Renormalization Group, Time and String Theory"
Djordje Minic , Virginia Tech
[Host: Paul Fendley]
"The CKM Experiment at Fermilab: Attacking the CKM Matrix Using Charged Kaons"
Craig Dukes , University of Virginia
[Host: H. Thacker]
"Quantum mechanics on noncommutative Riemann surfaces"
Bogdan Morariu , Rockefeller University
[Host: Paul Fendley]
"Zeroes of the neutrino mass matrix"
Paul Frampton , University of North Carolina, Chapel Hill
[Host: P. Q. Hung]
Wednesday, November 7, 2001
12:45 PM
Physics Building, Room 313
"Melting the Color Glass Condensate in Heavy Ions Collisions"
Raju Venugopalan , Brookhaven National laboratory
[Host: S. Liuti]
"Electroweak Breaking from the Bulk of Extra Dimensions"
Antonio Delgado , Johns Hopkins University
[Host: Marcos-Seco]
"A local Langevin equation for slow long distance modes in hot Yang-Mills"
Deitrich Bodeker , Brookhaven National Laboratory
[Host: Peter Arnold]
Thursday, April 26, 2001
4:00 PM
Physics Building, Room 204
"A Measurement of the (D+ --> K-bar*0 l+ nul) (D+ --> K-bar0 l+ nul) Branching Fractions"
Sang-Joon Lee , University of Minnesota
[Host: Harry Thacker]
"Physics of Decay KL --> pi+pi-e+e- at kTeV"
Alexander Golossanov , UVA - High Energy Physics
[Host: H. Thacker]
"The phase transition temperature of relativistic phi-4 theory"
Svyatoslav Tkachenko , University of Virginia - Department of Physics
[Host: Hank Thacker]
Wednesday, February 21, 2001
3:30 PM
Physics Building, Room 204
"Gravitational Radiation from Accreting Neutron Stars: Implications for Millisecond Pulsar Formation and LIGO"
Lars Bildsten , ITP, Santa Barbara
[Host: P. Q. Hung]
"High Power EUV Radiation Sources for Lithography"
Robert Rossmanith , Forschungszentrum Karlsruhe
[Host: Blaine Norum ]
"Reordering the Chiral Expansion - Solution of the Old Puzzle"
Martin Mojzis , Comunius University, Bratislava
[Host: Ivan Horvath]
"Present Status of LHCb An Experiment to Make Precision Studies of CP Violation in Beauty Hadron Decays"
Professor Tatsuya Nakada , CERN and Paul Scherrer Institute
[Host: Brad Cox]
Friday, April 28, 2000
2:00 PM
Physics Building, Room 203
"Dynamically Broken Topcolor - Building Higgs Bosons without Other Higgs Bosons"
Howard Georgi , Harvard University
[Host: P. Q. Hung]
Wednesday, March 22, 2000
3:00 PM
Physics Building, Room 204
"An Update on Nucleon Spin Structure Measurements at HERMES"
Geoffrey Court , University of Liverpool
[Host: Donald Crabb]
Thursday, March 9, 2000
3:30 PM
Physics Building, Room 204
"QCD and Dark Matter"
Prof. Sibaji Raha , Bose Institute, Calcutta and Brookhaven National laboratory, Upton, NY
[Host: P. K. Kabir]
"Recent Results from the NA48 Kaon Decay Experiment at CERN"
Professor Konrad Kleinknecht , Johannes Gutenberg University, Mainz, Germany
[Host: Brad Cox]
"Chiral Symmetry and Long Wavelength Dirac Eigenmodes in QCD"
John McCune , University of Virginia
[Host: Hank Thacker]
Wednesday, February 23, 2000
3:00 PM
Physics Building, Room 204
"Effective and Ineffective Field Theory in Nuclear Physics"
Tom Cohen , University of Maryland
[Host: J.V. Noble]
Thursday, February 17, 2000
4:00 PM
Physics Building, Room 204
"Supersymmetry Breaking in SO(10) models"
Pedro Mercadente , Florida State University
[Host: P. Q. Hung]
Wednesday, February 16, 2000
4:15 PM
Physics Building, Room 204
"The Angular Momentum Sum-Rule - - - Spin-Doctoring the Proton"
Ben White , University of Swansea
[Host: P. Q. Hung]
"Non-forward Parton Distribution and Deeply Virtual Compton Scattering"
Igor Musatov , Old Dominion University
Wednesday, November 17, 1999
3:00 PM
Physics Building, Room 204
"Quark-Hadron Duality - Recent results from Jefferson Lab"
Cynthia Keppel , Hampton University / Jefferson Lab
[Host: S. Luiti]
"Weak Matrix Elements in the Large Nc expansion of QCD "
Bill Bardeen , Fermilab
[Host: Thacker/Horvath]
To add a speaker, send an email to ecd3m@Virginia.EDU Include the seminar type (e.g. High Energy Physics Seminars), date, name of the speaker, title of talk, and an abstract (if available). [Please send a copy of the email to phys-speakers@Virginia.EDU.]