Speaker: Kevin Langhoff
Title: The Irreducible Axion Background
Room: 3024
Host: Luty
Abstract: Searches for dark matter decaying into photons constrain its lifetime to be many orders of magnitude larger than the age of the Universe. A corollary statement is that the abundance of any particle that can decay into photons over cosmological timescales is constrained to be much smaller than the cold dark-matter density. We show that an irreducible freeze-in contribution to the relic density of axions is in violation of that statement in a large portion of the parameter space. This allows us to set stringent constraints on axions in the mass range 100 eV - 100 MeV. Although I will focus on axions, the argument is more general and can be extended to, for instance, sterile neutrinos.
User:
High-Energy Seminars
Time:
4:10pm-5:10pm
Location:
PHY 285
Send Reminder:
Yes - 0 days 1 hour 0 minutes before start
Description:
Speaker: Albert De Roeck
Title: Forward detectors at the LHC for searches and high energy neutrinos measurements
Room: TBC (likely 285)
Host: Citron
Zoom: https://cern.zoom.us/j/62427334349?pwd=Y3cvcGZkRldvdEM5SzZZYnAvK1gxQT09
In 2022 two new detectors have been collecting data at the LHC for searches for BSM physics and to measure high energy neutrinos: FASER and SND@LHC. These new forward experiments have already reported first results this spring on first high energy neutrinos observed at the LHC and on a dark photon search. These experiment are also sensitive to axion-like particles, light dark matter particles, and in general to feebly interacting light long-lived particles.
The experiments will be described and physics prospects discussed. We use the experience of these new experiments to introduce the case for a generic forward physics program at the LHC, for neutrino physics, QCD studies and searches for BSM physics. We present a newly proposed project, called the Forward Physics Facility, a dedicated cavern about 600 meters away from the ATLAS interaction point which would host five new forward experiments and is scheduled to make use of the high luminosity LHC run around 2030.
