Abstract Details

Conference ID: ASI2017_1320
Title : Ongoing star-formation and stellar evolution in the active H II region Sh2-242
Authors and Co-Authors : Soumen Mondal, Somnath Dutta, S. N. Bose National Centre for Basic Sciences
Abstract Type : Poster
Abstract Category : Stars,ISM and the Galaxy
Abstract : Galactic H II regions concerns the formation and early evolution of stars of various masses over a time-scale of few million years. To understand the star formation activity in galactic H II regions, studies of the properties of various star-forming regions (SFRs) at different environments are essential. Sh2-242 is a faint and red nebulous region located at a distance of 2.1 kpc and excited by a known B0 V star, BD+26 980. An optically visible IRAS source, IRAS 05490+2658 lies at ∼ 5′ east of the H II region Sh2-242 and at a similar distance of 2.1 kpc. We aim to explore the young stellar population as well as to understand the structure and star formation history for the SFR Sh2-242 using optical, near-infrared (NIR) and mid-infrared (MIR) wavelengths. Using (J − H/H − K) NIR color excess diagram, we have identified more than 100 candidate members in the region Sh2-242. We estimated an average extinction Av ~ 3.8 mag towards Sh2-242 from field star decontamination method. From J vs (J − H) color-magnitude diagram, we have estimated the mass range of young stellar objects as 0.1-3.0 M⊙ having an average age of 2-3 Myr. From the different color composite images in NIR and MIR, it is apparent that the SFR Sh2-242 is not isolated, another two H II regions, LBN 182.30+00.07 and G182.4+00.2, may be associated with it. Further spectrophotometric analysis of few bright members are on-going for complete understanding of the region. We present here results from our preliminary analysis.