384 citations · 1.9k across the 70 of their papers we have counts for
51 papers · 1 filter
Very low scale Coleman-Weinberg inflation with non-minimal coupling
Kunio Kaneta, Osamu Seto, Ryo Takahashi
We study viable small-field Coleman-Weinberg (CW) inflation models with the help of non-minimal coupling to gravity. The simplest small-field CW inflation model (with a low-scale p…
Renormalization Group Improved Higgs Inflation with a Running Kinetic Term
Fuminobu Takahashi, Ryo Takahashi
We study a Higgs inflation model with a running kinetic term, taking account of the renormalization group evolution of relevant coupling constants. Specifically we study two types…
A White Paper on keV Sterile Neutrino Dark Matter
R. Adhikari, M. Agostini, N. Anh Ky +133
We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved - cosmology, astrophysics, nuclear, and par…
Gauge coupling unification in a classically scale invariant model
Naoyuki Haba, Hiroyuki Ishida, Ryo Takahashi +1
There are a lot of works within a class of classically scale invariant model, which is motivated by solving the gauge hierarchy problem. In this context, the Higgs mass vanishes at…
A model realizing inverse seesaw and resonant leptogenesis
Mayumi Aoki, Naoyuki Haba, Ryo Takahashi
We construct a model realizing the inverse seesaw mechanism. The model has two types of gauge singlet fermions in addition to right-handed neutrinos. A required Majorana mass scale…
Hierarchy problem, gauge coupling unification at the Planck scale, and vacuum stability
Yuya Yamaguchi
To solve the hierarchy problem of the Higgs mass, it may be suggested that there are no an intermediate scale up to the Planck scale except for the TeV scale. For this motivation,…
Search for new physics via photon polarization of
Naoyuki Haba, Hiroyuki Ishida, Tsuyoshi Nakaya +2
We suggest a discriminant analysis of new physics beyond the standard model through a detection of photon polarization in a radiative B meson decay. This analysis is investigated i…
Realization of the Lepton Flavor Structure from Point Interactions
Yukihiro Fujimoto, Kenji Nishiwaki, Makoto Sakamoto +1
We investigate a 5d gauge theory on with point interactions. The point interactions describe extra boundary conditions and provide three generations, the charged lepton mass…
Hierarchy problem, gauge coupling unification at the Planck scale, and vacuum stability
Naoyuki Haba, Hiroyuki Ishida, Ryo Takahashi +1
From the point of view of the gauge hierarchy problem, introducing an intermediate scale in addition to TeV scale and the Planck scale (…
Gravitational effects on vanishing Higgs potential at the Planck scale
Naoyuki Haba, Kunio Kaneta, Ryo Takahashi +1
We investigate gravitational effects on the so-called multiple point criticality principle (MPCP) at the Planck scale. The MPCP requires two degenerate vacua, whose necessary condi…
dark matter-philic Higgs for 3.5 keV X-ray signal
Naoyuki Haba, Hiroyuki Ishida, Ryo Takahashi
We suggest a new model of 7 keV right-handed neutrino dark matter inspired by a recent observation of 3.5 keV X-ray line signal in the XMM-Newton observatory. It is difficult to de…
Vanishing Higgs potential at the Planck scale in a singlet extension of the standard model
Naoyuki Haba, Hiroyuki Ishida, Kunio Kaneta +1
We discuss the realization of a vanishing effective Higgs potential at the Planck scale, which is required by the multiple-point criticality principle (MPCP), in the standard model…
Realization of lepton masses and mixing angles from point interactions in an extra dimension
Yukihiro Fujimoto, Kenji Nishiwaki, Makoto Sakamoto +1
We investigate a model on an extra dimension where plenty of effective boundary points described by point interactions (zero-thickness branes) are arranged. After suitably se…
Higgs inflation and Higgs portal dark matter with right-handed neutrinos
Naoyuki Haba, Hiroyuki Ishida, Ryo Takahashi
We investigate the Higgs inflation and the Higgs portal dark matter with the right-handed neutrino. The dark matter and the right-handed neutrino in the Higgs inflation play import…
Higgs inflation with singlet scalar dark matter and right-handed neutrino in light of BICEP2
Naoyuki Haba, Ryo Takahashi
We discuss the Higgs inflation scenario with singlet scalar dark matter and a right-handed neutrino. The singlet scalar and the right-handed neutrino play crucial roles for realizi…
Accurate renormalization group analyses in neutrino sector
Naoyuki Haba, Kunio Kaneta, Ryo Takahashi +1
We investigate accurate renormalization group analyses in neutrino sector between -oscillation and seesaw energy scales. We consider decoupling effects of top quark and Higgs bo…
Planck scale boundary conditions in the standard model with singlet scalar dark matter
Naoyuki Haba, Kunio Kaneta, Ryo Takahashi
We investigate Planck scale boundary conditions on the Higgs sector of the standard model with a gauge singlet scalar dark matter. We will find that vanishing self-coupling and Vel…
NNMSM Type-II and III
Naoyuki Haba, Kunio Kaneta, Ryo Takahashi
We suggest two types of extension of the standard model, which are the so-called next to new minimal standard model (NNMSM) type-II and -III. They can achieve gauge coupling unific…
Next to new minimal standard model
Naoyuki Haba, Kunio Kaneta, Ryo Takahashi
We suggest a minimal extension of the standard model, which can explain current experimental data of the dark matter, small neutrino masses and baryon asymmetry of the universe, in…
Renormalization group invariants in neutrino sector
Naoyuki Haba, Ryo Takahashi
We show renormalization group invariants in neutrino sector. These are found from a simple analytical discussion of Majorana mass matrix for light neutrinos. It is shown that the i…
Constraints on neutrino mass ordering and degeneracy from Planck and neutrino-less double beta decay
Naoyuki Haba, Ryo Takahashi
We investigate constraints on neutrino mass ordering and degeneracy by considering the first cosmological result based on Planck measurements of the cosmic microwave background. It…
Separate seesaw and its applications to dark matter and baryogenesis
Ryo Takahashi
We propose a new seesaw model in an extra-dimensional setup where only right-handed neutrinos are bulk fields. In the model, localizations of an extra-dimensional wave function and…
Minimal Neutrino Texture with Neutrino Mass Ratio and Cabibbo Angle
Yusuke Shimizu, Ryo Takahashi, Morimitsu Tanimoto
We present neutrino mass matrix textures in a minimal framework of the type-I seesaw mechanism where two right-handed Majorana neutrinos are introduced in order to reproduce experi…
Stability of Leptonic Self-complementarity
Naoyuki Haba, Kunio Kaneta, Ryo Takahashi
We investigate a stability of leptonic self-complementarity such that sum of three mixing angles in lepton sector is 90 degrees. Renormalization group equations in a context of min…