Photometric and spectroscopic study of the new FUor star V2493 Cyg

TL;DR

This study presents comprehensive photometric and spectroscopic observations of the FUor star V2493 Cyg, documenting its outburst from the beginning and analyzing its long-term brightness and spectral variability over several years.

Contribution

First detailed observation of V2493 Cyg's outburst from its onset across all spectral ranges, providing valuable data on its prolonged activity.

Findings

Outburst duration exceeds six years with a 5.1 mag amplitude.

Star maintained maximum brightness from 2013 to 2016.

Spectral lines, especially H alpha, showed significant variability.

Abstract

The recent results from photometric and spectroscopic study of the FUor star V2493 Cyg (HBC 722) are presented in the paper. The outburst of V2493 Cyg was registered during the summer of 2010 before the brightness of the star to reach the maximum value. V2493 Cyg is the first FUor object, whose outburst was observed from its very beginning in all spectral ranges. The recent photometric data show that the star keeps its maximum brightness during the period September 2013 - May 2016 and the recorded amplitude of the outburst is 5.1 mag. (V) Consequently, the outburst of V2493 Cyg lasts for more than six years. Our spectral observations showed strong variability in the profiles and intensity of emission lines especially for H alpha line. We expect that the interest in this object will increase in the coming years and the results will help to explore the nature of young stars.