H$\alpha$ emission line sources from VLT-MUSE in a low-metallicity star forming region -- Dolidze 25

Abstract

The process of accretion through circumstellar disks in young stellar objects is an integral part of star formation and the $H\alpha$ emission line is a prominent signature of accretion in low-mass stars. We present the detection and characterization of $H\alpha$ emission line sources in the central region of a distant, low-metallicity young stellar cluster - Dolidze 25 (at $\sim$ 4.5 kpc) - using medium-resolution optical spectra (4750-9350 Å ) obtained with the Multi-Unit Spectroscopic Explorer (MUSE) at the VLT. We have identified 14 potential accreting sources within a rectangular region of (2${}^{\prime }$ x 1${}^{\prime }$) towards the center of the cluster based on the detection of strong and broad emissions in $H\alpha$ as well as the presence of other emission lines such as [OI] and $H\beta$. Based on their positions in both photometric color-magnitude and color-color diagrams, we have also confirmed that these objects belong to the pre-main sequence phase of star formation. Our results were compared with the disk and diskless members of the cluster previously identified by Guarcello et al. (2021) using near-IR colors, and all sources they had identified as disks were confirmed to be accreting based on the spectroscopic characteristics.

References in corpus (8)

• The UKIRT Infrared Deep Sky Survey (UKIDSS)
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• Pre-main sequence accretion in the low metallicity Galactic star-forming region Sh 2-284
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Cited by in corpus (1)

• Determining stellar accretion rates from $P{a}_{\alpha }$ and $B{r}_{\beta }$ emission lines with JWST NIRSpec