The unusual photometric behavior of the new FUor star V2493 Cyg (HBC 722)

TL;DR

This paper documents the unique photometric behavior of V2493 Cyg, a FUor star, highlighting its prolonged outburst and brightness variations observed across multiple spectral ranges since 2010.

Contribution

It provides the first detailed, multi-year photometric observation of V2493 Cyg's outburst from its very beginning, revealing its unusual duration and brightness changes.

Findings

Outburst duration exceeds three years.

Brightness variations include multiple maxima and declines.

The amplitude of outburst reaches 5.1 magnitudes in V band.

Abstract

The recent results from photometric study of the new FUor star found in the field of NGC 7000/IC 5070 are presented in the paper. The outburst of V2493 Cyg in the summer of 2010 generated considerable interest among the astronomical community. V2493 Cyg is the first FUor object, whose outburst was observed from its very beginning in all spectral ranges. After reaching the firs maximum in September/October 2010, the brightness of V2493 Cyg declined slowly, having weakened by 1.45 mag. (V) by the spring/early summer of 2011. Since the autumn of 2011, another light increase occurred and the star became brighter by 1.8 mag. (V) until April 2013. The recent photometric data show that the star keeps its maximum brightness during the period April - August 2013 and the recorded amplitude of the outburst reaches Delta V=5.1 mag. Consequently, the outburst of V2493 Cyg lasts for more than three years. 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.