Conveners
Primordial Black Holes
- Nicholas Orlofsky (University of Wisconsin-Madison)
We investigate Hawking evaporation of a population of primordial black holes (PBHs) as a novel mechanism to populate a dark sector which consists of self-interacting scalar dark matter with pure gravitational coupling to the visible sector. We demonstrate that depending on initial abundance of PBHs and the dark matter mass, the dark sector can reach chemical equilibrium with a temperature...
Primordial Black Holes (PBHs) formed in the early universe could have an impact on all cosmological era from Big Bang Nucleosynthesis to the Cosmic Microwave Background and even galaxy formation, thus they are subject to a very stringent set of constraints over an extended mass range from $10^9$ to $10^{50}$ g. However, PBHs lighter than $10^9$ g are at present practically unconstrained,...
In this talk, I will present the phenomenology of dark-matter production in the case where it is both produced by a freeze-out or freeze-in mechanism and by the evaporation of primordial black holes. I will show that the presence of a vector mediator between the hidden and the visible sector affects the production of dark-matter particles as well as its phase space distribution. I will also...
We explicitly construct a double field inflationary model, which satisfies the latest PLANCK constraints at the CMB scales and produces the whole dark matter energy density as primordial black holes (PBHs), in the mass range 10^{-17}~M_{\odot}\lesssim M_{{}{\rm PBH}}\lesssim 10^{-13}~M{\odot}. The PBHs can be produced after the end of slow-roll inflation from the bubbles of true vacuum that...
We consider the axion flux emitted as Hawking radiation by primordial black holes (PBHs). If these axions are coupled with photons, they can convert into these particles in the cosmic magnetic fields. We explore the possible consequences of this mechanism on the cosmic X-ray background (CXB), the soft X-ray excess from galaxy clusters, and the reionization history of the Universe. We also...
In the early universe, primordial black holes (PBHs) can no longer be described by the simple Schwarzschild metric-- we need a metric which is locally surrounded by the cosmological fluid and asymptotically FLRW. It turns out that the phenomenology of PBHs is very sensitive to the choice of such a metric. In particular, the Thakurta metric stands out as perhaps the most justifiable metric for...
