122 citations · 1k across the 49 of their papers we have counts for
51 papers
Cosmic Birefringence from Large Lepton Asymmetry
Kentaro Kasai, Ippei Obata
Cosmic birefringence, the rotation of the polarization plane of CMB photons, provides an intriguing probe of physics beyond the Standard Model. In this paper, we investigate a vect…
Vector field dark matter search with Sagnac interferometer
Yuki Inoue, Quynh Lan Nguyen, Ippei Obata
We present the first calculation showing that a material-asymmetric Sagnac speed meter can improve quantum-noise-limited sensitivity to vector dark matter by nearly two order…
Dipolar power asymmetry in wide-angle correlations of galaxy density, velocity and ellipticity
Yusuke Mikura, Teppei Okumura, Ippei Obata +1
The large-scale structure of the universe has the potential to probe anomalies suggested by observations of the cosmic microwave background. In this work, we focus on a position-de…
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…
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…
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…