104 citations · 676 across the 37 of their papers we have counts for
7 papers · 1 filter
Enhancement of second-order gravitational waves at Q-ball decay
Shinta Kasuya, Masahiro Kawasaki, Kai Murai
The recent observation of He favors a large lepton asymmetry at the big bang nucleosynthesis. If Q-balls with a lepton charge decay after the electroweak phase transition, such…
Isotropic cosmic birefringence from early dark energy
Kai Murai, Fumihiro Naokawa, Toshiya Namikawa +1
A tantalizing hint of isotropic cosmic birefringence has been found in the cross-power spectrum of the cosmic microwave background (CMB) polarization data with a statistical…
Revisiting the Affleck-Dine mechanism for primordial black hole formation
Kentaro Kasai, Masahiro Kawasaki, Kai Murai
We study a primordial black hole (PBH) formation scenario based on the Affleck-Dine (AD) mechanism and investigate two PBH mass regions: motivated by the LIGO-V…
Gravitational waves detectable in laser interferometers from axion-SU(2) inflation
Tomohiro Fujita, Kaname Imagawa, Kai Murai
Chromo-natural inflation (CNI) is an inflationary model where an axion coupled with SU gauge fields acts as the inflaton. In CNI, the gauge fields have nonzero vacuum expectat…
Lepton Asymmetric Universe
Masahiro Kawasaki, Kai Murai
The recent observation of He implies that our universe has a large lepton asymmetry. We consider the Affleck-Dine (AD) mechanism for lepton number generation. In the AD mechani…
EMPRESS. VIII. A New Determination of Primordial He Abundance with Extremely Metal-Poor Galaxies: A Suggestion of the Lepton Asymmetry and Implications for the Hubble Tension
Akinori Matsumoto, Masami Ouchi, Kimihiko Nakajima +42
The primordial He abundance is a powerful probe of cosmology. Currently, is best determined by observations of metal-poor galaxies, while there are on…