165 citations · 2.5k across the 85 of their papers we have counts for
14 papers · 1 filter
High-scale SUSY from an R-invariant New Inflation in the Landscape
Masahiro Kawasaki, Masaki Yamada, Tsutomu T. Yanagida +1
We provide an anthropic reason that the supersymmetry breaking scale is much higher than the electroweak scale as indicated by the null result of collider experiments and observed…
Affleck-Dine baryogenesis just after inflation
Masaki Yamada
We propose a new scenario of Affleck-Dine baryogenesis where a flat direction in the MSSM generates B-L asymmetry just after the end of inflation. The resulting amount of baryon as…
Suppressing the QCD Axion Abundance by Hidden Monopoles
Masahiro Kawasaki, Fuminobu Takahashi, Masaki Yamada
We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there…
Affleck-Dine leptogenesis and its backreaction to inflaton dynamics
Masaki Yamada
We investigate the backreaction of the Affleck-Dine leptogenesis to inflaton dynamics in the F-term hybrid and chaotic inflation models in supergravity. We determine the lightest n…
Spontaneous Baryogenesis from Asymmetric Inflaton
Fuminobu Takahashi, Masaki Yamada
We propose a variant scenario of spontaneous baryogenesis from asymmetric inflaton based on current-current interactions between the inflaton and matter fields with a non-zero B-L…
Cosmologically safe QCD axion without fine-tuning
Masaki Yamada, Tsutomu T. Yanagida, Kazuya Yonekura
Although QCD axion models are widely studied as solutions to the strong CP problem, they generically confront severe fine-tuning problems to guarantee the anomalous PQ symmetry. In…
Can thermal inflation be consistent with baryogenesis in gauge-mediated SUSY breaking models?
Taku Hayakawa, Masahiro Kawasaki, Masaki Yamada
Thermal inflation is an attractive idea to dilute cosmic density of unwanted particles such as moduli fields which cause cosmological difficulties. However, it also dilutes preexis…
Strongly broken Peccei-Quinn symmetry in the early Universe
Fuminobu Takahashi, Masaki Yamada
We consider QCD axion models where the Peccei-Quinn symmetry is badly broken by a larger amount in the past than in the present, in order to avoid the axion isocurvature problem. S…
Cosmologically safe QCD axion as a present from extra dimension
Masahiro Kawasaki, Masaki Yamada, Tsutomu T. Yanagida
We propose a QCD axion model where the origin of PQ symmetry and suppression of axion isocurvature perturbations are explained by introducing an extra dimension. Each extra quark-a…
Thermalization Process after Inflation and Effective Potential of Scalar Field
Kyohei Mukaida, Masaki Yamada
We investigate the thermalization process of the Universe after inflation to determine the evolution of the effective temperature. The time scale of thermalization is found to be s…
Charged Q-balls in gauge mediated SUSY breaking models
Jeong-Pyong Hong, Masahiro Kawasaki, Masaki Yamada
It is known that after Affleck-Dine baryogenesis, spatial inhomogeneities of Affleck-Dine field grow into non-topological solitons called Q-balls. In gauge mediated SUSY breaking m…
Gravitational wave signals from short-lived topological defects in the MSSM
Ayuki Kamada, Masaki Yamada
Supersymmetric theories, including the minimal supersymmetric standard model, usually contain many scalar fields whose potentials are absent in the exact supersymmetric limit and w…
Observable dark radiation from cosmologically safe QCD axion
Masahiro Kawasaki, Masaki Yamada, Tsutomu T. Yanagida
We propose a QCD axion model that avoids the cosmological domain wall problem, introducing a global SU(3)_f family symmetry to which we embed the unwanted PQ discrete symmetry. The…
Affleck-Dine baryogenesis after D-term inflation and solutions to the baryon-DM coincidence problem
Masahiro Kawasaki, Masaki Yamada
We investigate the Affleck-Dine baryogenesis after D-term inflation with a positive Hubble-induced mass term for a B-L flat direction. It stays at a large field value during D-term…