54 citations · 96 across the 7 of their papers we have counts for
7 papers
Cosmological contribution from population III stars in ultracompact minihalos
Katsuya T. Abe
In this work, we investigate the effect of Population~III~(Pop.~III) stars in ultracompact minihalos~(UCMHs) on the cosmic ionization history using the Planck observation data. Alt…
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…
Population III star explosions and Planck 2018 data
Katsuya T. Abe, Hiroyuki Tashiro
We investigate the effect of the population III (Pop III) stars supernova explosion~(SN) on the high redshifts reionization history using the latest Planck data. It is predicted th…
Induced gravitational waves as a cosmological probe of the sound speed during the QCD phase transition
Katsuya T. Abe, Yuichiro Tada, Ikumi Ueda
The standard model of particle physics is known to be intriguingly successful. However their rich phenomena represented by the phase transitions (PTs) have not been completely unde…
The 21-cm signals from ultracompact minihalos as a probe of primordial small-scale fluctuations
Kunihiko Furugori, Katsuya Abe, Toshiyuki Tanaka +3
Ultracompact minihalos~(UCMHs) can form after the epoch of matter-radiation equality, if the density fluctuations of dark matter have significantly large amplitude on small scales.…
Sunyaev-Zel'dovich anisotropy due to Primordial black holes
Katsuya T. Abe, Hiroyuki Tashiro, Toshiyuki Tanaka
We investigate the Sunyaev-Zel'dovich (SZ) effect caused by primordial black holes (PBHs) on the cosmic microwave background (CMB) temperature fluctuations. The gas accreting on a…