collaborators

7 papers

hep-ph2026

Probing Majoron Dark Matter with Gravitational Wave Detectors

Ippei Obata, Tsutomu T. Yanagida

The Majoron is a hypothetical (pseudo) Nambu-Goldstone boson arising from the spontaneous breaking of a global lepton number symmetry, and is known as a candidate for dark matter i…

hep-ph2026

The COSMIC WISPers White Paper: The physics case for Weakly Interacting Slim Particles

Ariel Arza, Deniz Aybas, Shyam Balaji +124

Axions and other very weakly interacting slim particles (WISPs), with masses below 1 GeV, arise naturally in many extensions of the Standard Model of particle physics. In particula…

hep-th2026

On the Kalb-Ramond field with non-minimal coupling to gravity

Anamaria Hell, Ippei Obata

We consider a massive Kalb-Ramond field with a general non-minimal coupling to gravity. We first study the theory in flat space-time, taking into account the non-linearities. We sh…

astro-ph.CO2025

Implications of Cosmic Birefringence for Multi-Field ALP Dark Matter

Jialiang Shao, Ippei Obata, Dongdong Zhang

Cosmic birefringence, characterized by the observed rotation of the polarization plane of the cosmic microwave background (CMB) radiation, serves as a critical probe for testing th…

hep-ex2025

Adjusting optical cavity birefringence with wavelength tunable laser for axion searches

Hinata Takidera, Hiroki Fujimoto, Yuka Oshima +6

Axions have attracted attention as promising candidates for dark matter (DM). Although axions have been intensively searched for, they have not been observed yet. Recently, novel e…

hep-ph2025

Axionic defects in the CMB: birefringence and gravitational waves

Ricardo Z. Ferreira, Silvia Gasparotto, Takashi Hiramatsu +2

The evidence for a non-vanishing isotropic cosmic birefringence in recent analyses of the CMB data provides a tantalizing hint for new physics. Domain wall (DW) networks have recen…