collaborators

7 papers

hep-ph2025

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…

hep-ph2025

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…

astro-ph.CO2025

Stringent Constraints on Self-Interacting Dark Matter Using Milky-Way Satellite Galaxies Kinematics

Shin'ichiro Ando, Kohei Hayashi, Shunichi Horigome +2

Self-interacting dark matter (SIDM) has been proposed to address small-scale challenges faced by the cold dark matter (CDM) paradigm, such as the diverse density profiles observed…

hep-ph2025

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…

hep-ph2024

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…

hep-ph2024

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…