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 the global 21cm signal of neutral hydrogen. We use the global 21cm signal to constrain the abundance of spinning PBHs in mass range of [2 × 10 13 , 10 18 ] grams. We consider several extended PBH distribution models. Our results show that 21cm can set the most stringent PBH bounds in our mass window. Compared with constraints set by Planck cosmic microwave background (CMB) data, 21cm limits are more stringent by about two orders of magnitudes. PBHs with higher spin are typically more strongly constrained. Our 21cm constraints for the monochromatic mass distribution rule out spinless PBHs with initial mass below 1.4 × 10 17 g, whereas extreme Kerr PBHs with reduced initial spin of a 0 = 0.999 are excluded as the dominant dark matter component for masses below 6 × 10 17 g. We also derived limits for the log-normal, power-law and critical collapse distributions.

Future Constraints on Primordial Black Holes from XGIS-THESEUS

“…Based on the Hawking radiation, there exist cornucopia of constraints from non-observation of emission products from PBH of mass region ∼ 5 × 10 14 − 2 × 10 17 g which are presently evaporating. Previous works have constrained this mass range via absence of any excess in electron-positron pairs [16][17][18][19][20][21], non-observation of neutrino flux from currents detectors [17] as well as the upcoming ones [22][23][24][25], the γ-rays observations [16,[26][27][28][29], X-rays observations [26,30], observation of radiosignals [31,32], 21-cm observations [33][34][35] and heating of interstellar medium [36,37] (for in-depth discussion on similar such studies of PBH, refer to Ref. [38][39][40][41]).…”

Limits on primordial black holes detectability with Isatis: A BlackHawk tool

“…Other studies are based on the direct [23] or indirect detection of electrons-positrons [22,[24][25][26][27][28][29][30][31][32][33][34][35][36][37]; and finally there are some papers that focus on neutrino constraints [25,[38][39][40]. Most of the more recent studies now take into account the effect of having a non-zero PBH spin, which enhances the photon emission and thus results in more stringent constraints for Kerr (rotating) PBHs [9,13,18,19,25,28,32,37,40], or an extended PBH mass distribution, that should be more realistic regarding the channels of PBH formation [13,15,16,18,24,25,29,32,40]. Exotic studies have also derived constraints on non-standard (other than Kerr) PBHs [41][42][43] or PBH-DM mixed scenarios [44][45][46][47].…”

Primordial Black Hole Dark Matter in the Context of Extra Dimensions

“…The evaporation of PBHs during the epoch of star formation and reionization could leave imprints in the highredshift 21cm signal by heating and ionizing intergalactic gas. Several studies have presented current or future limits, considering the evaporation of 4-dimensional PBHs, either motivated by the recent detection of a deep 21cm absorption trough by the EDGES [110] experiment [111][112][113][114][115][116] or looking ahead to large-scale experiments such as the Square Kilometer Array [117]. Many other studies have examined the impact of matter accretion onto macroscopic PBHs that might seed early structure formation or produce X-ray backgrounds [118][119][120][121][122].…”