21-cm constraints on spinning primordial black holes

Abstract Hawking radiation from primordial black holes (PBH) can ionize and heat up neutral gas during the cosmic dark ages, leaving imprints on global 21-cm signal of hydrogen. We use to constrain abundance spinning PBHs in mass range [2 × 10 13 , 18 ] grams. consider several extended PBH distribution models. Our results show that set most stringent bounds our window. Compared with constraints by Planck microwave background (CMB) data, limits are more about two orders magnitudes. higher spin typically strongly constrained. for monochromatic rule out spinless initial below 1.5 17 g, whereas extreme Kerr reduced a 0 =0.999 excluded as dominant matter component masses 6 g. also derived log-normal, power-law critical collapse distributions.