Zobrazeno 1 - 10
of 1 411
pro vyhledávání: '"Kawasaki, Masahiro"'
We study a primordial black hole (PBH) formation model based on the framework of the inhomogeneous Affleck-Dine (AD) mechanism, which can explain the seeds of supermassive black holes (SMBHs). This model, however, predicts strong clustering of SMBHs
Externí odkaz:
http://arxiv.org/abs/2405.09790
We study the supersymmetric Q balls which decay at present and find that they create a distinctive spectrum of gamma rays at around O(10) MeV. The charge of the Q ball is lepton numbers in order for the lifetime to be as long as the present age of th
Externí odkaz:
http://arxiv.org/abs/2403.01675
Sterile neutrino is a fascinating candidate for dark matter. In this paper, we examine the Affleck-Dine (AD) leptogenesis scenario generating a large lepton asymmetry, which can induce the resonant production of sterile neutrino dark matter via the S
Externí odkaz:
http://arxiv.org/abs/2402.11902
Autor:
Kasai, Kentaro, Kawasaki, Masahiro, Kitajima, Naoya, Murai, Kai, Neda, Shunsuke, Takahashi, Fuminobu
We study a modification of the primordial black hole (PBH) formation model from axion bubbles. We assume that the Peccei-Quinn scalar rolls down in the radial direction from a large field value to the potential minimum during inflation, which suppres
Externí odkaz:
http://arxiv.org/abs/2310.13333
The stochastic gravitational wave background (SGWB) recently detected by the PTA collaborations could be the gravitational waves (GWs) induced by curvature perturbations. However, primordial black holes (PBHs) might be overproduced if the SGWB is exp
Externí odkaz:
http://arxiv.org/abs/2309.11398
Autor:
Kawasaki, Masahiro, Murai, Kai
Publikováno v:
JCAP01(2024)050
The existence of a stochastic gravitational wave background is indicated by the recent pulsar timing array (PTA) experiments. We study the enhanced production of second-order gravitational waves from the scalar perturbations when the universe experie
Externí odkaz:
http://arxiv.org/abs/2308.13134
The discrete symmetry $Z_4$ in the standard model (SM) with three right-handed neutrinos is free from the Dai-Freed anomaly. Motivated by this $Z_4$ symmetry, we constructed a topological inflation model consistent with all known constraints and obse
Externí odkaz:
http://arxiv.org/abs/2306.14579
Autor:
Kasai, Kentaro, Kawasaki, Masahiro, Kitajima, Naoya, Murai, Kai, Neda, Shunsuke, Takahashi, Fuminobu
We study the clustering of primordial black holes (PBHs) and axion miniclusters produced in the model proposed to explain the LIGO/Virgo events or the seeds of the supermassive black holes (SMBHs) in arXiv:2006.13137. It is found that this model pred
Externí odkaz:
http://arxiv.org/abs/2305.13023
Publikováno v:
JHEP 11 (2023) 106
When we impose the discrete symmetry in the standard model we have Dai-Freed global anomalies. However, interestingly if we introduce three right-handed neutrinos we can have an anomaly-free discrete $Z_4$ gauge symmetry. This $Z_4$ symmetry should b
Externí odkaz:
http://arxiv.org/abs/2304.10100
Autor:
Xu, Yi, Ouchi, Masami, Isobe, Yuki, Nakajima, Kimihiko, Ozaki, Shinobu, Bouché, Nicolas F., Wise, John H., Emsellem, Eric, Kusakabe, Haruka, Hattori, Takashi, Nagao, Tohru, Chiaki, Gen, Fukushima, Hajime, Harikane, Yuichi, Hayashi, Kohei, Hirai, Yutaka, Kim, Ji Hoon, Maseda, Michael V., Nagamine, Kentaro, Shibuya, Takatoshi, Sugahara, Yuma, Yajima, Hidenobu, Aoyama, Shohei, Fujimoto, Seiji, Fukushima, Keita, Hatano, Shun, Inoue, Akio K., Ishigaki, Tsuyoshi, Kawasaki, Masahiro, Kojima, Takashi, Komiyama, Yutaka, Koyama, Shuhei, Koyama, Yusei, Lee, Chien-Hsiu, Matsumoto, Akinori, Mawatari, Ken, Moriya, Takashi J., Motohara, Kentaro, Murai, Kai, Nishigaki, Moka, Onodera, Masato, Ono, Yoshiaki, Rauch, Michael, Saito, Tomoki, Sasaki, Rin, Suzuki, Akihiro, Takeuchi, Tsutomu T., Umeda, Hiroya, Umemura, Masayuki, Watanabe, Kuria, Yabe, Kiyoto, Zhang, Yechi
Publikováno v:
The Astrophysical Journal, Volume 961, Number 1, January 2024, Page 49-53
We present demography of the dynamics and gas-mass fraction of 33 extremely metal-poor galaxies (EMPGs) with metallicities of $0.015-0.195~Z_\odot$ and low stellar masses of $10^4-10^8~M_\odot$ in the local universe. We conduct deep optical integral-
Externí odkaz:
http://arxiv.org/abs/2303.12467