71 citations · 154 across the 8 of their papers we have counts for
35 papers
Baryon Asymmetric Universe from Spontaneous CP Violation
Kohei Fujikura, Yuichiro Nakai, Ryosuke Sato +1
Spontaneous CP violation, such as the Nelson-Barr (NB) mechanism, is an attractive scenario for addressing the strong CP problem while realizing the observed phase of the Cabibbo-K…
Cosmic Birefringence Triggered by Dark Matter Domination
Shota Nakagawa, Fuminobu Takahashi, Masaki Yamada
Cosmic birefringence is predicted if an axion-like particle (ALP) moves after the recombination. We show that this naturally happens if the ALP is coupled to the dark matter densit…
A natural and simple UV completion of the QCD axion model
Masaki Yamada, Tsutomu T. Yanagida
The novel PQ mechanism replaces the strong CP problem with some challenges in a model building. In particular, the challenges arise regarding i) the origin of an anomalous global s…
Trapping Effect for QCD Axion Dark Matter
Shota Nakagawa, Fuminobu Takahashi, Masaki Yamada
In the early universe, the potential of a scalar field can be significantly modified, and the scalar field may be trapped for a long time in a different location than the current v…
Wash-In Leptogenesis
Valerie Domcke, Kohei Kamada, Kyohei Mukaida +2
We present a leptogenesis mechanism based on the standard type-I seesaw model that successfully operates at right-handed-neutrino masses as low as a few 100 TeV. This mechanism, wh…
Gravitational Waves and Dark Radiation from Dark Phase Transition: Connecting NANOGrav Pulsar Timing Data and Hubble Tension
Yuichiro Nakai, Motoo Suzuki, Fuminobu Takahashi +1
Recent pulsar timing data reported by the NANOGrav collaboration may indicate the existence of a stochastic gravitational wave background around Hz. We explore a p…