High Energy Physics Seminars This Term
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, January 6, 2021
4:00 PM
Online, Room via Zoom
Note special room.
"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.
[Host: Chris Neu]
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, January 20, 2021
4:00 PM
Online, Room via Zoom
Note special room.
"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.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, February 3, 2021
4:00 PM
Online, Room via Zoom
Note special room.
"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.
Wednesday, February 10, 2021
4:00 PM
Online, Room via Zoom
Note special room.
Wednesday, February 17, 2021
3:30 PM
Physics Building, Room TBA
Note special time.
Note special room.
Wednesday, February 24, 2021
4:00 PM
Online, Room via Zoom
Note special room.
https://virginia.zoom.us/j/92287909487
Meeting ID: 922 8790 9487
Password: HEPseminar
Wednesday, March 3, 2021
4:00 PM
Online, Room via Zoom
Note special room.
"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, March 17, 2021
4:00 PM
Online, Room via Zoom
Note special room.
"Recent progress at the NOvA neutrino experiment"
Andrew Sutton , University of Virginia - Department of Physics
[Host: Craig Group]
TBA
Wednesday, March 24, 2021
4:00 PM
Physics Building, Room TBA
Note special room.
TBA
Wednesday, March 31, 2021
4:00 PM
Online, Room viz Zoom
Note special room.
TBA
Wednesday, April 7, 2021
4:00 PM
Physics Building, Room TBA
Note special room.
Wednesday, April 14, 2021
4:00 PM
Online, Room via Zoom
Note special room.
Wednesday, April 21, 2021
4:00 PM
Online, Room via Zoom
Note special room.
TBA
Wednesday, April 28, 2021
4:00 PM
Online, Room via Zoom
Note special room.
TBA
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.]