collaborators

5 papers

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

The James Webb Space Telescope NIRSpec-PRISM Transmission Spectrum of the Super-Puff, Kepler-51d

Jessica E. Libby-Roberts, Aaron Bello-Arufe, Zachory K. Berta-Thompson +14

Kepler-51 is a 500 Myr G dwarf hosting three "super-puffs" and one low-mass non-transiting planet. Kepler-51d, the coolest (T_eq ~ 350 K) transiting planet in this system, is also…

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…