148 citations · 683 across the 16 of their papers we have counts for
12 papers · 1 filter
Gravitational wave spectrum from kinks on infinite cosmic superstrings with Y-junctions
Yuka Matsui, Koichiro Horiguchi, Daisuke Nitta +1
We calculate the gravitational wave (GW) background spectra from kink propagation and kink-kink collisions on infinite cosmic superstrings. We take into account two characteristics…
Improved calculation of the gravitational wave spectrum from kinks on infinite cosmic strings
Yuka Matsui, Koichiro Horiguchi, Daisuke Nitta +1
Gravitational wave observations provide unique opportunities to search for cosmic strings. One of the strongest sources of gravitational waves is discontinuities of cosmic strings,…
Test of the Einstein equivalence principle with spectral distortions in the cosmic microwave background
Shun Arai, Daisuke Nitta, Hiroyuki Tashiro
The Einstein Equivalence Principle~(EEP) can be verified by the measurement of the spectral distortions of the Cosmic Microwave Background (CMB). The existence of energy-dependency…
Optimal limits on primordial magnetic fields from CMB temperature bispectrum of passive modes
Maresuke Shiraishi, Daisuke Nitta, Shuichiro Yokoyama +1
We investigate bounds on the strength of the primordial magnetic field (PMF) from the cosmic microwave background (CMB) bispectra of the intensity (temperature) modes induced from…
Parity Violation of Gravitons in the CMB Bispectrum
Maresuke Shiraishi, Daisuke Nitta, Shuichiro Yokoyama
We investigate the cosmic microwave background (CMB) bispectra of the intensity (temperature) and polarization modes induced by the graviton non-Gaussianities, which arise from the…
Formulation and constraints on decaying dark matter with finite mass daughter particles
Shohei Aoyama, Kiyotomo Ichiki, Daisuke Nitta +1
Decaying dark matter cosmological models have been proposed to remedy the overproduction problem at small scales in the standard cold dark matter paradigm. We consider a decaying d…