Sensitivities on nonspinning and spinning primordial black hole dark matter with global 21-cm troughs

Abstract

Detection of the global 21 cm signal arising from neutral hydrogen can revolutionize our understanding of the standard evolution of the Universe after recombination. In addition, it can also be an excellent probe of dark matter (DM). Among all the DM candidates, primordial black holes (PBHs) are one of the most well motivated. Hawking emission from low-mass PBHs can have a substantial effect on the thermal and ionization history of the early Universe, and that in turn can have an imprint on the global 21 cm signal. Recently EDGES has claimed a global 21 cm signal, though SARAS 3 has rejected that claim. In this work, we investigate the sensitivities on nonspinning and spinning PBHs arising from an EDGES-like measurement of the global 21 cm signal, and find that the sensitivities will be competitive with those arising from other astrophysical observables. We show that the sensitivities can be significantly strengthened depending on various uncertain astrophysical parameters. Besides, we also derive projections on the PBH density from the absorption trough expected during the Dark Ages. Our work shows that the near future unambiguous detection of the global 21 cm absorption troughs can be an excellent probe of PBH DM.

Doubly peaked induced stochastic gravitational wave background: testing baryogenesis from primordial black holes

“…[25][26][27][28][29][30][31][32]), formation of supermassive black holes [26,33,34], r-process nucleosynthesis [35] etc. Existence of PBHs in different mass ranges is constrained considerably from LIGO-Virgo observations [36], the observation diffuse supernova neutrino background and gamma ray background [37][38][39][40][41][42][43], gravitational microlensing observations [44][45][46], CMB observations [47][48][49], the detection of 21cm lines [50][51][52][53][54][55], gas heating in the interstellar medium [56,57] and etc. But there is still an open window of asteroid mass range (10 −16 − 10 −14 M ) where PBHs can provide entirety of dark matter [58].…”

Global 21-cm brightness temperature in viscous dark energy models

“…However, the net cooling due to the combination of VDE and that due to the baryon-DM interaction is capable of explaining the EDGES observation. Our work should motivate further studies of viscous dark energy models by taking into account additional phenomena such as PBH accretion [24,112], and the spinning effect of PBHs [45,113] in estimation of the 21-cm brightness temperature. Future space-based and ground-based experiments related to 21-cm physics will help to shed more light on such unknown aspects of cosmological dynamics.…”

“…It may be mentioned here that another recent observation SARAS [44] is at variance with the EDGES's results. However, as there is no publicly available data from the SARAS experiment, we use the EDGES result only in our calculations, similar in approach to other recent works [7,8,11,25,45]. In order to perform an analysis of the interplay of the effect of VDE, primordial black hole (PBH) evaporation and the baryon-dark matter interaction on the 21-cm temperature, we consider PBHs with near present era evaporating mass range ∼ 10 14 ≤ M BH 2 × 10 15 g, along with a widely used form of the baryon -dark matter scattering cross-section [6,7,9,11,12,[46][47][48].…”

Axion-like particles from primordial black hole evaporation and their detection in neutrino experiments

“…Hawking's famous discovery tells that PBHs with the mass ∼ 10 15 g would thermally radiate elementary particles [22] and thus they cannot provide all the observed abundance of DM [23]. The emitted particles such as gamma-rays, neutrinos and e ± in the evaporation process suffer from a variety of cosmological constraints [24][25][26][27][28][29][30][31][32][33][34][35][36]. The elementary DM particles emitted from the present PBHs were also studied in very recent works [37][38][39].…”