We present the discovery of twelve metal-poor and distant pre-main sequence (PMS) candidates in the dwarf irregular galaxy Wolf-Lundmark-Melotte (WLM)~968 kpc away, at a present-day metallicity of [Fe/H] around −0.9. These candidates have masses between 1.25-5 M⊙, with ages <10 Myr, and exhibit significant near-infrared excesses at 2.5 and 4.3 μm. They are concentrated within a cluster roughly 10 pc (2'') across situated in the HII region [HM95]-9. These are the most distant and metal-poor PMS stars known, and can offer new quantitative insights into star formation at low-metallicities.
@article{arxiv.2501.17097,
title = {Discovery of metal-poor and distant pre-main sequence candidates in WLM with JWST},
author = {Venu M. Kalari and Ricardo Salinas and Morten Andersen and Guido De Marchi and Monica Rubio and Jorick S. Vink and Hans Zinnecker},
journal= {arXiv preprint arXiv:2501.17097},
year = {2025}
}
Comments
Accepted for publication in ApJ Letters. Comments welcome. 6 pages, 4 figures, and 1 table