collaborators

5 papers

astro-ph.SR2026

Discovery of a Low-Mass Companion to the Accelerating Star HIP 53005 with Strongly Conflicting Mass Estimates

Taichi Uyama, Thayne Currie, Jerry W. Xuan +22

We present the discovery of a low-mass companion located at 0\farcs{}85 () from the early-type 1.2 Gyr-old star HIP 53005 using direct imagi…

astro-ph.IM2026

PyIRD: A Python-Based Data Reduction Pipeline for Subaru/IRD and REACH

Yui Kasagi, Hajime Kawahara, Ziying Gu +4

PyIRD is a Python-based pipeline for reducing spectroscopic data obtained with IRD (InfraRed Doppler; Kotani et al. (2018)) and REACH (Rigorous Exoplanetary Atmosphere Characteriza…

astro-ph.EP2025

Unveiling the Atmosphere of HR 7672 B from the Near-Infrared High-Resolution Spectrum Using REACH/Subaru

Yui Kasagi, Yui Kawashima, Hajime Kawahara +12

Characterizing the atmospheres of exoplanets and brown dwarfs is crucial for understanding their atmospheric physics and chemistry, searching for biosignatures, and investigating t…

astro-ph.EP2025

Measurement of Methane Line Broadening in Hot Hydrogen/Helium Atmospheres at = 1.60-1.63 μm for Substellar Object Spectroscopy

Ko Hosokawa, Takayuki Kotani, Hajime Kawahara +4

Recent high-dispersion spectroscopy from ground-based telescopes and high-precision spectroscopy from space observatories have enabled atmospheric observations of substellar object…

astro-ph.EP2025

Probing 2D Asymmetries of an Exoplanet Atmosphere from Chromatic Transit Variation

Shotaro Tada, Hajime Kawahara, Yui Kawashima +2

We propose a new method for investigating atmospheric inhomogeneities in exoplanets through transmission spectroscopy. Our approach links chromatic variations in conventional trans…