Speaker: Weishuang Linda Xu
Title: The continuum and the line: new analyses of Fermi gamma-ray data
Room: 3024
Host: Da Liu
Abstract:
The search for dark matter is now indisputably a multi-disciplinary and multi-decadal effort. While the models and methods under consideration have expanded tremendously, astrophysical indirect detection remains one of the best and sometimes only ways to challenge the well-worn--but undeniably compelling--notion of the thermal relic WIMP. In this talk I will present two gamma-ray searches (alike in dignity), weaponizing the last 14 years of Fermi data to search for hints of dark matter physics.
Speaker: Soubhik Kumar
Title: Classical Cosmological Collider Physics
Room: 3024
Host: Da Liu
Abstract: Massive field excitations during the inflationary era, imprinted on cosmological correlation functions, can provide us with a unique opportunity to probe heavy degrees of freedom far beyond the reach of terrestrial colliders. In the simplest inflationary models, any such cosmological collider signal is exponentially suppressed for particles much heavier than the inflationary Hubble scale, limiting the potential reach of such new physics searches. In this talk, I will discuss how primordial features on the inflationary landscape can naturally excite very heavy modes. Respecting the current bounds on the power spectrum, I will show that this mechanism can extend the reach of the cosmological collider by one or two orders of magnitude. This can bring various well-motivated high-scale models, such as GUTs, within the observational window for various near-term surveys.
User:
High-Energy Seminars
Time:
4:10pm - 5:10pm
Send Reminder:
Yes - 0 days 4 hour 0 minutes before start
Description:
Speaker: Henry Lubatti (U. Washington)
Title: Long-lived particles – Messengers from a Hidden Sector
Host: Chertok
Room: 285
Abstract: The completion of the Standard Model (SM) has left us with key central issues suggesting that “physics beyond the Standard Model (BSM) is likely and, in some cases, unavoidable” as noted in the Snowmass report of the Physics Beyond the Standard Model at Energy Frontier. Dark Matter, matter - antimatter asymmetry of the universe, very light neutrino masses etc. have led to many theoretical constructs that attempt to address these issues. All allow for long-lived and feebly interacting particles, which may be connected to DM and reside in a hidden sector that has no charge in common with the SM sector. The hidden sector may have a rich phenomenology like the SM sector. Such possibilities have triggered a large effort in ATLAS, CMS and LHCb to search for evidence of long-lived particles that have decays displaced from the IP. Unfortunately, the LLP models do not predict the lifetime; thus, we need to search over a large range of lifetimes with perhaps the only limit being Big Bang Nucleosynthesis that occurs about 0.1 s after the Big Bang. To cover such a wide variety of signals and lifetimes in a SM background free environment, several auxiliary experiments have been proposed. In this talk I will review some of the LHC detector searches and proposed auxiliary experiments.
User:
High-Energy Seminars
Time:
1:30pm - 3:00pm
Send Reminder:
Yes - 3 days 5 hour 0 minutes before start
Description:
Speaker: Simon Knapen
Title: Dark Matter scattering in low threshold detectors
Room: 3024
Host: Da Liu
Abstract: Upcoming and existing detector technology makes it possible to search for dark matter candidates well below the mass range of the traditional WIMP searches. This implies that Debroglie wavelength of the dark matter is comparable or larger than the interparticle spacing in a noble liquid or solid state target. Collective effects in the target material must therefore be included in scattering rate calculations, which take place on the interface between particle physics and theoretical material science.
