135 citations · 2.2k across the 88 of their papers we have counts for
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Primordial black hole dark matter in the presence of p-wave WIMP annihilation
Kenji Kadota, Hiroyuki Tashiro
We study the allowed primordial black hole (PBH) dark matter abundance in the mixed dark matter scenarios consisting of PBHs and self-annihilating weakly interacting massive partic…
Free-free background radiation from accreting primordial black holes
Hiroyuki Tashiro, Katsuya T. Abe, Teppei Minoda
Baryonic gas falling onto a primordial black hole (PBH) emits photons via the free-free process. These photons can contribute the diffuse free-free background radiation in the freq…
Constraint on the early-formed dark matter halos using the free-free emission in the Planck foreground analysis
Katsuya T. Abe, Teppei Minoda, Hiroyuki Tashiro
We provide a new constraint on the small-scale density fluctuations, evaluating the diffuse background free-free emission from dark matter halos in the dark ages. If there exists a…
CMB and 21cm bounds on early structure formation boosted by primordial black hole entropy fluctuations
Hiroyuki Tashiro, Kenji Kadota
The dark matter (DM) can consist of the primordial black holes (PBHs) in addition to the conventional weakly interacting massive particles (WIMPs). The Poisson fluctuations of the…
Constraining the luminosity function of active galactic nuclei through the reionization observations in the SKA era
Kai T. Kono, Taichi Takeuchi, Hiroyuki Tashiro +2
Ultraviolet (UV) and X-ray photons from active galactic nuclei (AGNs) can ionize hydrogen in the intergalactic medium (IGM). We solve radiative transfer around AGNs in high redshif…
Constraining Mixed Dark-Matter Scenarios of WIMPs and Primordial Black Holes from CMB and 21-cm observations
Hiroyuki Tashiro, Kenji Kadota
We consider the dark matter (DM) scenarios consisting of the mixture of WIMPs and PBHs and study how much fraction of the total DM can be PBHs. In such scenarios, PBHs can accrete…