Seminario de Samuel Witte (IFIC, Valencia)
"Signatures of Primordial Black Holes in 21cm Cosmology"
Current and near future 21cm cosmological surveys promise to offer a wealth of information about state of the Universe during the early stage of reionization and the cosmic dawn, cosmological epochs which have yet to be directly probed. The 21cm signal produced during these epochs is remarkably sensitive to the state of the IGM, and thus can provide a strong probe of any exotic model that modifies either the temperature evolution of the medium or the formation of structure. In this talk I will focus on the potential signatures arising from a population of ~ solar mass primordial black holes (PBHs) that account for a subdominant fraction of the dark matter. I will illustrate three distinct effects produced by these PBHs and comment on the expected sensitivity to the 21cm power spectrum from experiments like HERA (Hydrogen Epoch of Reionization Array) and SKA-Low, showing that 21cm observations may improve existing constraints by multiple orders of magnitude. Should time permit, I will comment on techniques being developed that will allow for a greater weather of information to be extracted from the data, and will greatly ease computational difficulties associated with predicting the 21cm signal at high redshifts.
Fecha: jueves 9 de mayo de 2019
Lugar: Seminario de Física Teórica