Conveners
Dark Sectors: Cosmological Aspects 2
- Barmak Shams Es Haghi (University of Utah Department of Physics & Astronomy)
Magnetically charged black holes are interesting solutions of the Standard Model and general relativity. They may possess a “hairy” electroweak-symmetric corona outside the event horizon, which speeds up their Hawking radiation and leads them to become nearly extremal on short timescales. Their masses could range from the Planck scale up to the Earth mass. I will present various methods to...
I examine cosmological and astrophysical signatures of a “dark baryon,” a neutral fermion that mixes with the neutron, deriving new, powerful limits from primordial nucleosynthesis and the cosmic microwave background. Additionally, neutrons in a neutron star could decay slowly to dark baryons, providing a novel source of heat that is constrained by measurements of pulsar temperatures. I...
I present a detailed study of the confinement phase transition in a dark sector with a SU(N) gauge group and a single generation of dark heavy quark. I focus on heavy enough quarks such that their abundance freezes out before the phase transition and the phase transition is of first-order. I show that during this phase transition the quarks are trapped inside contracting pockets of the...
We present two distinct models which rely on 1st order phase transitions in a dark sector. The first is a minimal model for baryogenesis which employs a new dark SU(2) gauge group with two doublet Higgs bosons, two lepton doublets, and two singlets. The singlets act as a neutrino portal that transfers the generated baryon asymmetry to the Standard Model. The model predicts extra relativistic...
In the usual approach to the determination of dark matter thermal relic abundance an assumption of local thermal equilibrium is made. In this talk I will discuss how to go beyond this assumption and will introduce DRAKE — a numerical precision tool that can trace not only the DM relic density, but also its velocity dispersion and full phase space distribution function. I will review the...
Observations of the early Universe indicate a Universe expanding today at a (Hubble) rate which is significantly slower than what is measured locally via supernovae, if the ΛCDM model is assumed. Furthermore, the amplitude of matter fluctuations at late times measured by cosmic shear surveys is smaller than what is inferred from the same early Universe observations, assuming the ΛCDM...
