635 citations · 6.2k across the 159 of their papers we have counts for
148 papers · 1 filter
Heavy Pseudo-Dirac Doublet Dark Matter and Non-Thermal Leptogenesis in Light of the LZ Event
Masahiro Ibe, Jun Miyamoto
Motivated by the recent LZ candidate nuclear-recoil event, we study pseudo-Dirac electroweak doublet dark matter in the mass range --, where bounds from s…
Radiative Breaking of Two-Zero Neutrino Mass Minors: Revisiting the Model
Masahiro Ibe, Jun Miyamoto, Satoshi Shirai
The two-zero minor structure predicted by flavor symmetries is usually discussed as a tree-level relation among low-energy neutrino parameters. We point out that this relation can…
Fermion Multiplicities at the GUT Scale: A Statistical Study of Unification and Proton Decay
Akifumi Chitose, Ko Hirooka, Masahiro Ibe +1
We study the impact of multiple vector-like fermions in SU(5) grand unified theory (GUT). Threshold effects from extra fermions allow the observed gauge couplings to be consistentl…
Flavor Symmetry and Proton Decay in PeV-Scale Supersymmetry
Akifumi Chitose, Masahiro Ibe, Satoshi Shirai
Supersymmetry beyond the TeV scale offers several theoretical and phenomenological advantages, such as accommodating the observed Higgs mass and alleviating the flavor and CP probl…
Do Cosmic String Segments Emit Gravitational Waves?
Akifumi Chitose, Masahiro Ibe, Shunsuke Neda +1
Cosmic strings are predicted in various extensions of the Standard Model, including grand unified theories. Depending on the symmetry-breaking pattern, they can be either topologic…
Cosmic Strings in Multi-Step Symmetry Breaking
Akifumi Chitose, Masahiro Ibe, Satoshi Shirai +1
We investigate cosmic strings arising from a hierarchical gauge symmetry breaking sequence, $\mathrm{SU}(2) \times \mathrm{U}(1) \rightarrow \mathrm{U}(1) \times \mathrm{U}(1) \rig…
Global Neutrino Constraints on the Minimal U(1) Model
Masahiro Ibe, Satoshi Shirai, Keiichi Watanabe
We examine the minimal U(1) gauge model in light of the latest neutrino data, including neutrino oscillations, cosmological observations, direct mass measurements, and…
Comprehensive Bayesian Exploration of Froggatt-Nielsen Mechanism
Masahiro Ibe, Satoshi Shirai, Keiichi Watanabe
The Froggatt-Nielsen (FN) mechanism successfully explains the hierarchical structure of fermion Yukawa couplings by introducing a U(1) flavor symmetry with distinct charge assignme…
Nucleon Decay as a Probe of Flavor Symmetry: The Case of Fake Unification
Masahiro Ibe, Satoshi Shirai, Keiichi Watanabe
This paper explores nucleon decay within the framework of a "fake Grand Unified Theory (GUT)" combined with the Froggatt-Nielsen (FN) mechanism. In this fake GUT framework, quarks…
Gravitational Waves from Metastable Cosmic Strings in Supersymmetric New Inflation Model
Akifumi Chitose, Masahiro Ibe, Shunsuke Neda +1
Recent observations by pulsar timing arrays (PTAs) indicate a potential detection of a stochastic gravitational wave (GW) background. Metastable cosmic strings have been recognized…
Small Instanton Effects on Composite Axion Mass
Takafumi Aoki, Masahiro Ibe, Satoshi Shirai +1
This paper investigates the impact of small instanton effects on the axion mass in composite axion models. In particular, we focus on the Composite Accidental Axion (CAA) models, w…
Revisiting Metastable Cosmic String Breaking
Akifumi Chitose, Masahiro Ibe, Yuhei Nakayama +2
Metastable cosmic strings appear in models of new physics with a two-step symmetry breaking , where and . They decay via the monopole-antimono…
Precise Estimate of Charged Higgsino/Wino Decay Rate
Masahiro Ibe, Yuhei Nakayama, Satoshi Shirai
Higgsinos and Winos in the supersymmetric Standard Model are prime candidates for dark matter due to their weakly interacting nature. The mass differences between their charged com…
Interactions of electrical and magnetic charges and dark topological defects
Akifumi Chitose, Masahiro Ibe
We consider a model of dark photon which appears as a result of the successive symmetry breaking SU(2)U(1), where various types of topological defects…
Muon and non-thermal leptogenesis in model
Shintaro Eijima, Masahiro Ibe, Kai Murai
The gauged symmetry is the simplest possibility to explain the observed muon , while being consistent with the neutrino oscillations through the seesaw mechan…
Precise Estimate of Charged Wino Decay Rate
Masahiro Ibe, Masataka Mishima, Yuhei Nakayama +1
The Wino is an triplet Majorana fermion and a well-motivated dark matter candidate. The mass difference between the charged and the neutral Winos is small than…
More on Fake GUT
Masahiro Ibe, Satoshi Shirai, Motoo Suzuki +2
It is remarkable that the matter fields in the Standard Model (SM) are apparently unified into the representations. A straightforward explanation of this fact is t…
Cosmological Constraints on Dark Scalar
Masahiro Ibe, Shin Kobayashi, Yuhei Nakayama +1
We discuss cosmological constraints on a dark scalar particle mixing with the Standard Model Higgs boson. We pay particular attention to the dark scalar production process when the…
Gauge Kinetic Mixing and Dark Topological Defects
Takashi Hiramatsu, Masahiro Ibe, Motoo Suzuki +1
We discuss how the topological defects in the dark sector affect the Standard Model sector when the dark photon has a kinetic mixing with the QED photon. In particular, we consider…
Chiral Composite Asymmetric Dark Matter
Masahiro Ibe, Shin Kobayashi, Keiichi Watanabe
The asymmetric dark matter (ADM) scenario solves the baryon-dark matter coincidence problem when the dark matter (DM) mass is of GeV. Composite ADM models based on…
Muon in Gauge Mediation without SUSY CP Problem
Masahiro Ibe, Shin Kobayashi, Yuhei Nakayama +1
We discuss gauge mediated supersymmetry breaking models which explain the observed muon anomalous magnetic moment and the Higgs boson mass simultaneously. The successful explanatio…
On Stability of Fermionic Superconducting Current in Cosmic String
Masahiro Ibe, Shin Kobayashi, Yuhei Nakayama +1
Recently, the chiral superconductivity of the cosmic string in the axion model has gathered attention. The superconductive nature can alter the standard understanding of the cosmol…
Proton Decay in Product Group Unification
Jason L. Evans, Masahiro Ibe, Tsutomu T. Yanagida
Product group unification is an attractive alternative to simple grand unification. It solves the infamous doublet-triplet splitting problem and the dimension-5 proton decay proble…
Cosmological Constraint on Vector Mediator of Neutrino-Electron Interaction in light of XENON1T Excess
Masahiro Ibe, Shin Kobayashi, Yuhei Nakayama +1
Recently, the XENON1T collaboration reported an excess in the electron recoil energy spectrum. One of the simplest new physics interpretation is a new neutrino-electron interaction…