activity
20242026
collaborators

8 papers

astro-ph.GA2026

The GALAH Survey: Neutron-Capture Elemental Abundances for 350,000 Gaia-RVS spectra and the Chemodynamics of Accreted Structures

Pradosh Barun Das, Daniel B. Zucker, Aldo Mura-Guzmán +16

We present a comprehensive data-driven spectroscopic analysis of 357,415 red giant stars using Gaia DR3 Radial Velocity Spectrometer (RVS) spectra (8460-8700 A; ),…

astro-ph.CO2026

Fifty years of primordial helium abundances: A statistical reanalysis

Nabil Husain, Richard de Grijs, Giuseppe Bono

The primordial helium mass fraction, , is a key observational pillar of Big Bang nucleosynthesis and a sensitive probe of early-Universe physics. Over the past severa…

astro-ph.SR2025

Optical spectroscopic signatures of the red giant evolutionary state

Ella Xi Wang, Melissa Ness, Thomas Nordlander +17

Modern spectroscopic surveys output large data volumes. Theoretical models provide a means to transform the information encoded in these data to measurements of physical stellar pr…

astro-ph.SR2025

Photometric activity cycles in fast-rotating stars: Revisiting the reality of stellar activity cycle branches

Deepak Chahal, Devika Kamath, Richard de Grijs +2

We aim to detect activity cycles in young main-sequence stars, analogous to the 11-year solar cycle, using combined photometric survey data. This research will enhance our understa…

astro-ph.GA2025

The HASHTAG project II. Giant molecular cloud properties across the M31 disc

Yikai Deng, Zongnan Li, Zhiyuan Li +17

We present a study of giant molecular cloud (GMC) properties in the Andromeda galaxy (M31) using CO(3-2) data from the James Clerk Maxwell Telescope (JCMT) in selected regions acro…

astro-ph.GA2025

The GALAH Survey: Stellar parameters and abundances for 800,000 Gaia RVS spectra using GALAH DR4 and The Cannon

Pradosh Barun Das, Daniel B. Zucker, Gayandhi M. De Silva +15

Analysing stellar parameters and abundances from nearly one million Gaia Data Release 3 (DR3) Radial Velocity Spectrometer (RVS) spectra poses challenges due to the limited spectra…