Zobrazeno 1 - 10
of 68
pro vyhledávání: '"Koji Ishiwata"'
Autor:
Koji Ishiwata, Kentaro Nomura
Publikováno v:
Journal of High Energy Physics, Vol 2024, Iss 10, Pp 1-33 (2024)
Abstract We investigate collective excitations in magnetic topological insulators (TIs) and their impact on axion detection. In the three-dimensional TI model with the Hubbard term, the effective action of magnons and amplitude modes is formulated by
Externí odkaz:
https://doaj.org/article/ce0304fd0f5446c580812507b246ff2a
Publikováno v:
Journal of High Energy Physics, Vol 2023, Iss 8, Pp 1-18 (2023)
Abstract We study baryogenesis in a hybrid inflation model which is embedded to the minimal supersymmetric model with right-handed neutrinos. Inflation is induced by a linear combination of the right-handed sneutrinos and its decay reheats the univer
Externí odkaz:
https://doaj.org/article/0cf38224e86f4770a6ba1569d12c58d2
Publikováno v:
Journal of High Energy Physics, Vol 2022, Iss 11, Pp 1-30 (2022)
Abstract We consider a supergravity model that has the modular A 4 symmetry and discuss the interplay between the neutrino mixing and inflation. The model contains right- handed neutrinos that have the Majorana masses and additional Yukawa couplings
Externí odkaz:
https://doaj.org/article/8704a0987d544ed2aa3e1da74a1c290d
Autor:
Yoshihiro Gunji, Koji Ishiwata
Publikováno v:
Journal of High Energy Physics, Vol 2019, Iss 9, Pp 1-27 (2019)
Abstract We consider an extended version of superconformal subcritical hybrid inflation model by introducing three right-handed neutrinos that have the Majorana mass terms. In the model one of the right-handed sneutrinos plays a role of the inflaton
Externí odkaz:
https://doaj.org/article/365e8086203a44f1a9e3365fdc2baa0e
Autor:
Koji Ishiwata, Takashi Toma
Publikováno v:
Journal of High Energy Physics, Vol 2018, Iss 12, Pp 1-15 (2018)
Abstract In the standard model extended by a single complex scalar boson with a softly broken global U(1) symmetry, a pseudo Nambu-Goldstone boson becomes a candidate for dark matter. In this paper, we discuss the direct detection of the pseudo Nambu
Externí odkaz:
https://doaj.org/article/a8fc4b1cc9764b02a490ad8cc5fdd2a7
Autor:
Koji Ishiwata
Publikováno v:
Physics Letters B, Vol 782, Iss , Pp 367-371 (2018)
We consider D-term hybrid inflation in the framework of superconformal supergravity. In part of the parameter space, inflation continues for subcritical inflaton field value. Consequently, a new type of inflation emerges, which gives predictions for
Externí odkaz:
https://doaj.org/article/3dbdf48d77c040eb9813697bb38d1e51
Autor:
Kazuhiro Endo, Koji Ishiwata
Publikováno v:
Physics Letters B, Vol 749, Iss C, Pp 583-588 (2015)
Classical scale invariance is one of the possible solutions to explain the origin of the electroweak scale. The simplest extension is the classically scale-invariant standard model augmented by a multiplet of gauge singlet real scalar. In the previou
Externí odkaz:
https://doaj.org/article/1f90faa6e31c48aa84273f84e521657b
Publikováno v:
Journal of High Energy Physics
We consider a supergravity model that has the modular $A_4$ symmetry and discuss the interplay between the neutrino mixing and inflation. The model contains right-handed neutrinos that have the Majorana masses and additional Yukawa couplings to the w
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::91818a44c7da081831f023b1cb763116
http://arxiv.org/abs/2208.10086
http://arxiv.org/abs/2208.10086
Publikováno v:
Physical Review D, 106(10):103014. American Institute of Physics
We investigate the primordial curvature perturbation by the observation of dark matter substructure. Assuming a bump in the spectrum of the curvature perturbation in the wavenumber of k>1 Mpc^{-1}, we track the evolution of the host halo and subhalos
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2af10eeb899f1b343ed263df3dc507ed
http://arxiv.org/abs/2207.05747
http://arxiv.org/abs/2207.05747
Autor:
Koji Ishiwata
We study the axion in three-dimensional topological insulators with magnetic impurities under finite temperature. We find a stable antiferromagnetic ground state and ferromagnetic metastable state. In both magnetic states, the mass of the axion is fo
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::797a10c0c614671f0d918654116e02a7
http://arxiv.org/abs/2206.00841
http://arxiv.org/abs/2206.00841