collaborators

5 papers

astro-ph.EP2024

[N I] 10400/10410 Å Lines as Possible Disk Wind Tracers in a Young Intermediate-Mass Star

Haruki Katoh, Chikako Yasui, Yuji Ikeda +10

In this study, we performed high-resolution near-infrared (NIR) spectroscopy (R = 28,000; -1.35 m) with a high signal-to-noise ratio on HD 200775, a very young (${\sim…

astro-ph.EP2024

A High-Resolution Non-Detection of Escaping Helium In The Ultra-Hot Neptune LTT 9779b: Evidence for Weakened Evaporation

Shreyas Vissapragada, Patrick McCreery, Leonardo A. Dos Santos +16

The recent discovery of ``ultra-hot'' ( day) Neptunes has come as a surprise: some of these planets have managed to retain gaseous envelopes despite being close enough to th…

astro-ph.IM2024

WARP: The Data Reduction Pipeline for the WINERED spectrograph

Satoshi Hamano, Yuji Ikeda, Shogo Otsubo +8

We present a data reduction pipeline written in Python for data obtained with the near-infrared cross-dispersed echelle spectrograph, WINERED, which yields a 0.911.35 m spect…

astro-ph.GA2023

The globular cluster VVV CL002 falling down to the hazardous Galactic centre

D. Minniti, N. Matsunaga, J. G. Fernandez-Trincado +15

Context. The Galactic centre is hazardous for stellar clusters because of the strong tidal force. Supposedly, many clusters were destroyed and contributed stars to the crowded stel…

astro-ph.SR2023

Metallicities of Classical Cepheids in the Inner Galactic Disk

N. Matsunaga, D. Taniguchi, S. S. Elgueta +14

Metallicity gradients refer to the sloped radial profile of metallicities of gas and stars and are commonly seen in disk galaxies. A well-defined metallicity gradient of the Galact…