Speaker: Djuna Croon (TRIUMF)
Title: New Physics and the Black Hole Mass Gap
Host:
Zoom: https://zoom.us/j/186024391
Abstract: In this talk I will demonstrate the potential of the black hole mass gap to probe new physics. The mass gap, in which no black holes can be formed, is a standard prediction of stellar structure theory. I will show that new physics that couples to the Standard Model can act as an additional source of energy loss in the cores of population-III stars, dramatically altering their evolution, resulting in large shifts of the gap. The gravitational wave observations by the LIGO/Virgo collaboration will bring the edges of the black hole mass gap in sight in the coming years, making this a promising novel probe of new physics.
User:
High-Energy Seminars
Time:
4:10pm - 5:10pm
Description:
Speaker: Tomi Akindele, LLNL
Topic: Antineutrinos as a Nuclear Safeguards Tool
Host: Svoboda
Zoom: Robert C Svoboda is inviting you to a scheduled Zoom meeting.
Topic: DENS/HEP/NP Seminar
Time: Nov 10, 2020 04:00 PM Pacific Time (US and Canada)
To date, antineutrino experiments built for the purpose of demonstrating a nonproliferation capability have typically employed organic scintillator, and been situated as close to the core as possible - typically a few meters to tens of meters distant, and have not exceeded a few tons in size.
One problem with this approach is that proximity to the reactor core requires accommodation by the host facility. Water Cherenkov detectors located offsite, at distances of a few kilometers or greater, may facilitate non-intrusive monitoring and verification of reactor activities over a large area.
As the standoff distance increases, the detector target mass must scale accordingly. This talk quantifies the degree to which a kiloton-scale gadolinium-doped water Cherenkov detector can exclude the existence of undeclared reactors within a specified radial distance, and remotely detect the presence of a hidden reactor in the presence of declared reactors, by verifying the operational power and standoff distance.
A Feldman-Cousins based likelihood analysis was used to quantify the detector's ability to exclude the existence of undeclared reactors. A 1-kton scale Water Cherenkov detector can exclude gigawatt-scale nuclear reactors up to tens of kilometers. When attempting to identify the specific location of a reactor, the detector response and analysis cannot delineate between the reactor power and baseline.
Description:
Veterans Day
User:
High-Energy Seminars
Time:
1:30pm - 2:30pm
Send Reminder:
Yes - 0 days 8 hour 0 minutes before start
Description:
Speaker: Jesse Thaler (MIT)
Title: The Hidden Geometry of Particle Collisions
Host:
Zoom: https://zoom.us/j/186024391
Abstract:
In this talk, I explain how various concepts and techniques in quantum field theory and collider physics can be naturally translated into a new geometric language. Using the energy mover's distance, which quantifies the minimal amount of "work" required to rearrange one event into another, we can define a distance between pairs of collider events. This distance can then be used to triangulate the "space" of collider events and rigorously define various geometric objects. Many well-known collider observables, jet algorithms, and pileup mitigation schemes have a simple geometric interpretation, as does the important concept of infrared and collinear safety. Intriguingly, these ideas can be lifted from a distance between events into a distance between theories, with potential relevance for visualizing and interpreting data from the LHC.
User:
High-Energy Seminars
Time:
11:00am - 12:00pm
Send Reminder:
Yes - 0 days 8 hour 0 minutes before start
Description:
Speaker: Gauthier Durieux (CERN)
Title: Massive amplitude approach to the standard-model effective field theory
Host:
Zoom: https://zoom.us/j/186024391
Abstract:
On-shell methods trivialize the representation of particles to provide an efficient description of their interactions, exempt from gauge or field redefinition redundancies. Applications to effective field theories led to new insights (e.g. into non-renormalizations and theory characterizations) as well as simpler methods (e.g. for operator bases constructions). The little-group-covariant treatment of massive spinors now allows for a systematic on-shell description of the standard-model effective field theory (SMEFT) from its broken phase. Putting this program on firm grounds, we bootstrapped non-renormalizable electroweak three-point amplitudes. The electroweak symmetry was explicitly seen to emerge from the requirement of perturbative unitarity. A full example of four-point amplitude was worked out, including both factorizable and contact-term contributions. The involved construction of independent massive contact terms was then addressed. These advances pave the way for a massive amplitude approach to the SMEFT.
User:
High-Energy Seminars
Time:
4:10pm - 5:10pm
Description:
Speaker: Teal Pershing, LLNL
Title: The ANNIE Experiment: Measuring the
neutron multiplicity of neutrino-nucleus
interactions
Host: Svoboda
Zoom: TBD
Abstract:Accurate modeling and tagging of inelastic charged-current neutrino interactions is critical to numerous physics measurements, including proton decay, neutrino oscillation parameter measurements, and neutrino interaction cross-section measurements. One known indicator of a neutrino interaction’s inelasticity is the presence of final-state neutrons, which are often challenging to detect. The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) is a gadolinium-doped water Cherenkov detector which is sensitive to final-state neutrons, and will measure the neutron multiplicity of neutrino charged-current interactions. ANNIE will also demonstrate the first use of Large Area Picosecond PhotoDetectors (LAPPDs) on a neutrino beam line for improved event reconstruction. This seminar will provide an overview of the ANNIE experiment and the physics motivating ANNIE’s neutron multi- plicity measurement. The experimental results from ANNIE’s background characterization will be presented, as well as the first calibration and neutrino beam data from ANNIE.
User:
High-Energy Seminars
Time:
1:30pm - 2:30pm
Description:
Speaker:
Title:
Host: Da Liu
Zoom: https://zoom.us/j/186024391
Abstract:
User:
High-Energy Seminars
Time:
1:30pm - 2:30pm
Send Reminder:
Yes - 0 days 8 hour 0 minutes before start
Description:
Speaker: Tongyan Lin (UC San Diego)
Title: Direct detection of sub-GeV dark matter with the Migdal effect in semiconductors
Host:
Zoom: https://zoom.us/j/186024391
Abstract:
As direct detection experiments expand the search for sub-GeV dark matter and lower their energy thresholds, the many-body physics of crystals can be increasingly important and also be used to enhance discovery potential. In this talk, I will discuss the Migdal effect in semiconductors, which is the creation of charge signals from inelastic dark matter-nucleus scattering. The Migdal effect has previously been studied in atomic targets, and used to set limits in liquid Xe experiments. Because of the smaller gap for electron excitations, we find that the rate for the Migdal effect is much higher in semiconductors, and accounting for it can significantly improve the reach of experiments.
Election Day