Characterizing the Low-Mass Pre-Main-Sequence Population in the Low-Metallicity Star-Forming Region Dolidze 25 Using VLT-MUSE

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 ($M<1M_{\odot }$) in the exceptionally metal-poor cluster Dolidze~25 ($Z\approx 0.2Z_{\odot }$), using VLT/MUSE observations to probe accretion processes and disk evolution in a subsolar environment. We identify 132 cluster members using a combination of \textit{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, luminosities enabling robust estimates of stellar masses and ages. Mass accretion rates (${\dot{M}}_{\mathrm{acc}}$) derived from H$\hat{I}\pm$ emission span $10^{-10}$--$10^{-8}{M}_{\odot }{\mathrm{yr}}^{-1}$ with a median value of \(8 \times 10^{-10}\,M_\odot\,\mathrm{yr}^{-1}\). These rates are comparable to those in solar-metallicity regions of 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 \(T_\mathrm{eff}\) (by approximately \(300\,\mathrm{K}\)) and \(A_V\) (by around \(0.5\,\mathrm{mag}\)), 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.