CPC Seminar: Dark matter freeze-in produces large post-inflationary isocurvature

  • Nov. 7, 2022, 2:00 pm US/Central
  • DIR/ Curia II-WH2SW - Wilson Hall 2nd fl South West

This activity or event is open to badged Fermilab personnel.

Speaker: Kim Berghaus
Institution/University: Stonybrook
Title/Abstract: Dark matter freeze-in produces large post-inflationary isocurvature

In this talk I will show that the nonthermal nature of dark matter freeze-in production leads to large, totally correlated dark matter-photon isocurvature perturbations, which are imprinted in anisotropies of the cosmic microwave background (CMB). Isocurvature is typically expected from inflationary physics but the isocurvature from freeze-in arises post inflation. Using millicharged dark matter as a benchmark model I will discuss how to calculate the amplitude of the generated isocurvature from a Lagrangian description of the dark matter freeze-in process. I will present novel results excluding millicharged dark matter as the sole dark matter component for masses between 1 MeV – 10 GeV, using current CMB observations from Planck. I’ll conclude by commenting on the broader implications of this new avenue for exploring fundamental dark matter physics.

Zoom: https://fermipoint.fnal.gov/service/seminars

If you are interested in connecting to the talk remotely without a Fermilab Services account, you can contact Dylan Temples, dtemples@fnal.gov.