The OVz stars in NGC 346: distribution, stellar parameters and insights into low-metallicity effects

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Arango, Leidy, Arias, Julia, Holgado, Gonzalo, Ferrero, Gabriel, Putkuri, Cristina, Morrell, Nidia
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915427934797824
author Arango, Leidy
Arias, Julia
Holgado, Gonzalo
Ferrero, Gabriel
Putkuri, Cristina
Morrell, Nidia
author_facet Arango, Leidy
Arias, Julia
Holgado, Gonzalo
Ferrero, Gabriel
Putkuri, Cristina
Morrell, Nidia
contents OVz stars are identified by their optical spectra, in which the He II 4686 absorption line is stronger than any other He line. This spectral characteristic suggests that these stars may be less luminous, less evolved, and located closer to the zero-age main sequence (ZAMS). Although their evolutionary status is still debated, OVz stars are key candidates for understanding the earliest stages of massive star evolution. In this study, we analyze OVz stars in the star-forming regions NGC 346 in the Small Magellanic Cloud (SMC) and 30 Doradus in the Large Magellanic Cloud (LMC), aiming to determine their physical properties and investigate the role of low metallicity in the emergence of the Vz peculiarity. We identified a sample of OVz and OV stars in NGC 346 using spectra obtained with the Magellan Echellette (MagE) spectrograph at Las Campanas Observatory. Spectral classification was based on the equivalent width ratios of key He lines. Quantitative spectroscopic analyses were carried out using the IACOB-BROAD and IACOB-GBAT/FASTWIND tools. For consistency, previously identified OV and OVz stars in 30 Doradus were reclassified following the same criteria.
format Preprint
id arxiv_https___arxiv_org_abs_2506_19190
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle The OVz stars in NGC 346: distribution, stellar parameters and insights into low-metallicity effects
Arango, Leidy
Arias, Julia
Holgado, Gonzalo
Ferrero, Gabriel
Putkuri, Cristina
Morrell, Nidia
Solar and Stellar Astrophysics
Astrophysics of Galaxies
OVz stars are identified by their optical spectra, in which the He II 4686 absorption line is stronger than any other He line. This spectral characteristic suggests that these stars may be less luminous, less evolved, and located closer to the zero-age main sequence (ZAMS). Although their evolutionary status is still debated, OVz stars are key candidates for understanding the earliest stages of massive star evolution. In this study, we analyze OVz stars in the star-forming regions NGC 346 in the Small Magellanic Cloud (SMC) and 30 Doradus in the Large Magellanic Cloud (LMC), aiming to determine their physical properties and investigate the role of low metallicity in the emergence of the Vz peculiarity. We identified a sample of OVz and OV stars in NGC 346 using spectra obtained with the Magellan Echellette (MagE) spectrograph at Las Campanas Observatory. Spectral classification was based on the equivalent width ratios of key He lines. Quantitative spectroscopic analyses were carried out using the IACOB-BROAD and IACOB-GBAT/FASTWIND tools. For consistency, previously identified OV and OVz stars in 30 Doradus were reclassified following the same criteria.
title The OVz stars in NGC 346: distribution, stellar parameters and insights into low-metallicity effects
topic Solar and Stellar Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2506.19190