Rotation rates of pre-main sequence stars: role of circumstellar disk

Abstract

Photometric variability with new high-cadence, long-duration data has drawn a huge interest to explore the time domain behaviour of young stellar objects since the last few decades. Here we provide an overview of optical photometric observations of the young clusters, identification of variable nature from their light curves, characterization of their circumstellar disk. Based on our studies, we find that 50-65% of young stars are variable in our studied regions. Most of the periodic young stars have periods less than 10 days. Disk-bearing stars have relatively larger amplitudes than the older population, which indicate that the young stellar variability could be due to the effect of the hotspot, asymmetric disk obscuration, accretion outbursts or any other structural modification in the inner disk regions.