| Authors : | Saumya Gupta, Jessy Jose, Surhud More, Swagat R.Das, Gregory Herczeg, Manash R Samal, Guo Zhen, Prem Prakash |
| Abstract : | Circumstellar disks are significant by-products of star formation and their evolution eventually gives way to the formation of planets around the host stars. Hence, the environment in which these disks evolve in turn suggests the huge diversity of exoplanetary system architectures that are being discovered. Thus, deep comprehensive studies of young Galactic star forming regions where the feedback driven cluster environment plays a crucial role in star formation, disk evolution and planet formation are the need of the hour. Cygnus OB2, at 1.6 kpc from the Sun and with ~ 200 OB-stars hosts extreme environmental conditions analogous to extra-galactic star forming regions and hence, is an ideal laboratory to explore the effect of stellar feedback on surrounding young low mass population. We perform a comprehensive multi-wavelength study of a 1.5 deg diameter region centered at Cygnus OB2, using the deepest and the widest optical photometry obtained with 8m Subaru Hyper Suprime-Cam (HSC), near-IR (UKIDSS), mid-IR (Spitzer) and Chandra X-ray photometry to study the pre-main sequence population reaching down to brown-dwarf limit including a significant census of disk-bearing and diskless objects. We use machine learning techniques to identify the cluster members and estimate physical parameters of the sources. We perform a statistical interpretation on the role of various factors like age, mass, incident UV radiation, stellar density on disk evolution in the region and compare the disk properties with other nearby star forming regions of diverse properties in terms of density and UV radiation strength. Since, most of such past studies have either been restricted to nearby clusters or limited by sensitivity of the data, this work is a pioneering step towards understanding the role of several external factors on young low mass stellar population in a massive Galactic star forming region. |
