Interaction of Accretion and Circumstellar Extinction as a Cause of Unusual Variability in the WTTS Star V715 Per

Abstract

We present new results of our photometric and spectroscopic monitoring of the WTTS star V715 Per that is located in the young cluster IC 348 and exhibits a complex pattern of variability. We show that the variability of the H\(\alpha\) line equivalent width is modulated with the rotation period of the star and is in antiphase with its brightness variations. This serves as a confirmation of the previously proposed model for the photometric variability of V715 Per based on variable circumstellar extinction in the inner disk at the corotation radius. According to our estimates, the radical change in the pattern of variability occurred after 2010 is attributable with a high probability to changes in the rate of accretion in the system. Our new photometric data have shown the end of the long fading of the star observed in the period 2017–2023 and caused by the occultation of an extended dusty structure in the outer disk. The refined period of the low-amplitude variability component is \(5.22^{\textrm{d}}\) and showed stability over the entire series of observations