135 citations · 2.2k across the 88 of their papers we have counts for
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Cosmological signatures of tilted isocurvature perturbations: reionization and 21cm fluctuations
Toyokazu Sekiguchi, Hiroyuki Tashiro, Joseph Silk +1
We investigate cosmological signatures of uncorrelated isocurvature perturbations whose power spectrum is blue-tilted with spectral index 2<p<4. Such an isocurvature power spectrum…
High redshift signatures in the 21 cm forest due to cosmic string wakes
Hiroyuki Tashiro, Toyokazu Sekiguchi, Joseph Silk
Cosmic strings induce minihalo formation in the early universe. The resultant minihalos cluster in string wakes and create a "21 cm forest" against the cosmic microwave background…
CMB distortion anisotropies due to the decay of primordial magnetic fields
Koichi Miyamoto, Toyokazu Sekiguchi, Hiroyuki Tashiro +1
We investigate the power spectrum of the distortion of Cosmic Microwave Background (CMB) due to the decay of the primordial magnetic fields. It is known that there are two-types of…
Search for CP Violating Signature of Intergalactic Magnetic Helicity in the Gamma Ray Sky
Hiroyuki Tashiro, Wenlei Chen, Francesc Ferrer +1
The existence of a cosmological magnetic field could be revealed by the effects of non-trivial helicity on large scales. We evaluate a CP odd statistic, , using gamma ray data o…
Constraints on primordial magnetic fields from CMB distortions in the axiverse
Hiroyuki Tashiro, Joseph Silk, David J. E. Marsh
Measuring spectral distortions of the cosmic microwave background (CMB) is attracting considerable attention as a probe of high energy particle physics in the cosmological context,…
Galactic Faraday rotation effect on polarization of 21 cm lines from the epoch of reionization
Soma De, Hiroyuki Tashiro
Redshifted 21 cm signal from neutral hydrogen is one of the most competitive probes of the epoch of reionization (EoR). Unpolarized 21 cm radiation acquires a certain level of line…