activity
20242026
collaborators

6 papers

astro-ph.EP2026

The mass of TOI-1883 b: A low density super-Neptune in the ridge regime transiting an early-M dwarf

Izuru Fukuda, Norio Narita, Akihiko Fukui +36

Recent large-scale transit surveys conducted by space telescopes such as Kepler and TESS have revealed a vast number of exoplanets, uncovering the diversity of their population. On…

astro-ph.SR2026

Unraveling Year-Long Radial Velocity Variations in Red Clump Region -- I: Comprehensive analysis of a K0 Giant star, 2 Draconis

Udomlerd Srisuchinwong, Jianzhao Zhou, Huan-Yu Teng +18

Slow-rotating evolved stars frequently exhibit radial velocity (RV) variations on annual timescales, complicated by instrumental systematics and aliasing in the one-year regime. He…

astro-ph.EP2025

The mass of TOI-654 b: A short-period sub-Neptune transiting a mid-M dwarf

Kai Ikuta, Norio Narita, Takuya Takarada +40

Sub-Neptunes are small planets between the size of the Earth and Neptune. The orbital and bulk properties of transiting sub-Neptunes can provide clues for their formation and evolu…

astro-ph.EP2025

Atmospheric retrieval of Subaru/IRD high-resolution spectrum of the archetype T-type brown dwarf Gl 229 B

Yui Kawashima, Hajime Kawahara, Yui Kasagi +14

Brown dwarfs provide a unique opportunity to study atmospheres and their physical and chemical processes with high precision, especially in temperature ranges relevant to exoplanet…

astro-ph.HE2024

Evolution of Accretion Disk Structure of the Black Hole X-ray Binary MAXI J1820070 during the Rebrightening Phase

Tomohiro Yoshitake, Megumi Shidatsu, Yoshihiro Ueda +18

To understand the evolution of global accretion disk structure in the ``rebrightening'' phase of MAXI J1820070, we perform a comprehensive analysis of its near infrared/optical/…

astro-ph.HE2024

Multiwavelength Observations of the Black Hole X-ray Binary MAXI J1820070 in the Rebrightening Phase

Tomohiro Yoshitake, Megumi Shidatsu, Yoshihiro Ueda +14

We report the results of quasi-simultaneous multiwavelength (near-infrared, optical, UV, and X-ray) observations of the Galactic X-ray black hole binary MAXI J1820+070 performed in…