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arXiv · 2608.25170

ABYSS. IV. Identifying signatures of stellar youth in APOGEE spectra

Valentina Bonilla Villalobos·Marina Kounkel·Joseph Mullen·Eleonora Zari·Alexandre Roman-Lopes·Keivan Stassun·Ricardo López-Valdivia·Jinyoung S. Kim·Mojgan Aghakhanloo·Facundo Pérez Paolino·Jonathan C. Tan·Jesús Hernández
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Abstract

We develop a convolutional neural network classifier that performs spectroscopic identification of stellar youth (<40 Myr) in APOGEE spectra. This classifier is sensitive to several youth-related features, including rotational broadening, which is common in younger stars, and to several discrete lines that appear to be indicative of a very spotted photosphere. The model is successful at identifying youth across a wide range of stars, achieving its strongest performance at discriminating young M and K dwarfs, while maintaining useful discriminatory power for hotter stars as well. This work enables more robust separation of pre-main-sequence stars from more evolved sources in the field even when they have comparable Teff and log(g), providing a reliable means to substantially reduce contamination in photometrically selected YSO candidates. In addition to constructing a classifier for APOGEE spectra, we also perform classification of young stars in optical BOSS spectra.

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Valentina Bonilla Villalobos, Marina Kounkel, Joseph Mullen, Eleonora Zari, Alexandre Roman-Lopes, Keivan Stassun, Ricardo López-Valdivia, Jinyoung S. Kim, Mojgan Aghakhanloo, Facundo Pérez Paolino, Jonathan C. Tan, Jesús Hernández. 2026-08-25. ABYSS. IV. Identifying signatures of stellar youth in APOGEE spectra. https://doi.org/10.3847/1538-3881%2Fae9d5f

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