Pre-Main Sequence stars in the star forming complex Sh 2-284

Abstract

Located at the galactic anticenter, Sh 2-284 is a HII region which harbors several young open clusters; Dolidze 25, a rare metal poor (Z~0.004) young cluster, is one of these. Given its association with Sh 2-284, it is reasonable to assume the low metallicity for the whole HII region. Sh~2-284 is expected to host a significant population of Pre-Main Sequence (PMS) stars of both low and intermediate mass stars (Herbig Ae stars). We aim at characterizing these stars by means of a spectroscopic and photometric survey conducted with VIMOS@VLT and complemented with additional optical and infrared observations. In this survey we selected and characterized 23 PMS objects. We derived the effective temperature, the spectral energy distribution and luminosity of these objects; using theoretical PMS evolutionary tracks, with the appropriate metallicity, we estimated the mass and the age of the studied objects. We also estimated a distance of 4 Kpc for Sh 2-284 by using spectroscopic parallax of 3 OB stars. From the age determination we concluded that triggered star formation is in act in this region. Our results show that a significant fraction of the young stellar objects (YSOs) may have preserved their disk/envelopes, in contrast with what is found in other recent studies of low-metallicity star forming regions in the Galaxy. Finally, among the 23 bona fide PMS stars, we identified 8 stars which are good candidates to pulsators of the delta Scuti type.

accepted for publication in MNRAS

References in corpus (5)

• Young, Low-Mass Brown Dwarfs with Mid-Infrared Excesses
• Open clusters as key tracers of Galactic chemical evolution. III. Element abundances in Berkeley 20, Berkeley 29, Collinder 261, and Melotte 66
• The evolution of stars in the Taurus-Auriga T association
• The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds.X. The Chamaeleon II Pre-Main Sequence Population as Observed With IRAC and MIPS
• Discovery of non-radial pulsations in the spectroscopic binary Herbig Ae star RS Cha

Cited by in corpus (16)

• Elemental abundances of low-mass stars in the young clusters 25 Ori and lambda Ori
• Photometric determination of the mass accretion rates of pre-main sequence stars. V. Recent star formation in the 30 Dor nebula
• Molecular cloud distances based on the MWISP CO survey and Gaia DR2
• Pre-main sequence accretion in the low metallicity Galactic star-forming region Sh 2-284
• Dispersal timescale of protoplanetary disks in the low-metallicity young cluster Dolidze 25
• Open cluster Dolidze 25: Stellar parameters and the metallicity in the Galactic Anticentre
• Molecular Environments of Three Large Supernova Remnants in the Third Galactic Quadrant: G205.5+0.5, G206.9+2.3, and G213.0-0.6
• Photometric determination of the mass accretion rates of pre-main sequence stars. VI. The case of LH 95 in the Large Magellanic Cloud
• CoRoT\,102699796, the first metal-poor Herbig Ae pulsator: a hybrid $\delta$ Sct-$\gamma$ Dor variable?
• CoRoT 102749568: mode identification in a delta Scuti star based on regular spacings
• Protoplanetary discs around sun-like stars appear to live longer when the metallicity is low
• Spectroscopic characterization of X-ray emitting young stars associated with the Sh 2-296 nebula
• Star formation history of Canis Major OB1 - II. A bimodal X-ray population revealed by XMM-Newton
• Testing Hadronic Models of Gamma Ray Production at the Core of Cen A
• Spitzer Mid-infrared Study of Sh 2-208: Evolution of Protoplanetary Disks in Low-metallicity Environments
• Accretion and Outflows in Young Stars with CUBES