State of the Universe

Mass Distributions of PBHs in the light of 21cm brightness temperature

by Dr. Upala Mukhopadhyay (Indian Statistical Institute (ISI), Kolkata,)

Friday, January 13, 2023 from to (Asia/Kolkata)
at Zoom : Meeting ID: 825 1295 6967 Passcode: 384194
The evaporation of primordial black holes (PBHs) via Hawking radiation influences the evolution of Intergalactic Medium by heating up the latter which consequently affects the 21cm signal from neutral Hydrogen atoms. In this work, we have considered EDGES observational data for 21cm line from the era of cosmic dawn to constrain the mass and the abundance of PBHs. In this context, two different PBH mass distributions namely, power law and lognormal mass distributions are considered to estimate the effects of PBH evaporation on the 21cm brightness temperature T21. The impacts of dark matter-baryon interactions on T21 are also considered in this work along with the influences of PBH evaporation. Furthermore, an attempt has been made to formulate a distribution function for PBH masses. This has been addressed by associating with every calculated T21 value corresponding to a pair of values of PBH mass and initial PBH mass fraction, a probability weightage considering the range of T21 (at z ∼ 17.2) given by EDGES experiment.