Work

Characterizing the Low-mass Pre-main-sequence Population in the Low-metallicity Star-forming Region Dolidze 25 Using VLT-MUSE

Year: 2026

Type: article

Abstract: The metallicity of the star-forming environment is a fundamental parameter shaping the evolution of protoplanetary disks and the formation of planetary systems, yet its influence remains poorly constrained. We present a spectroscopic study of low-mass pre-main-sequence (PMS) stars ( M < 1 M ⊙ ) in the exceptionally metal-poor cluster Dolidze 25 ( Z ≈ 0.2 Z ⊙ ), using Very Large Telescope/MUSE observations to probe accretion processes and disk evolution in a subsolar environment. We identify 132 cluster members using a combination of Gaia astrometry and spectroscopic youth indicators, including lithium absorption and Balmer emission. The stellar parameters are derived using low-metallicity BT-Settl models yielding effective temperatures, extinctions, and luminosities enabling robust estimates of stellar masses and ages. Mass accretion rates ( M ̇ acc ) derived from H α emission span 10 −10 –10 −8 M ⊙ yr −1 with a median value of 8 × 10 −10 M ⊙ yr −1 . These rates are comparable to those in solar-metallicity regions of a similar age, such as Lupus and Orion, indicating minimal metallicity dependence in accretion processes. Our analysis shows that using solar-metallicity templates to fit low-metallicity stars leads to systematic overestimations of T eff (by approximately 300 K) and A V (by around 0.5 mag), underscoring the importance of employing metallicity-matched models for reliable characterization in low- Z environments. We present flux-calibrated, extinction-corrected spectra of these metal-poor PMS stars as a valuable resource for future investigations of disk evolution in subsolar regimes.

Source: The Astrophysical Journal

DOI: 10.3847/1538-4357/ae28cf