NEAR-IR PHOTOMETRIC AND OPTICAL SPECTROSCOPIC STUDY OF THE FU ORIONIS OBJECT V582 AURIGAE

Abstract

We carried out near-IR photometric and optical spectroscopic observations of V582 Aur, which isa FU Orionis type object, to investigate any periodic and/or aperiodic variations. We obtained lightcurves on the scale of a night and a year, in J, H and Ks bands with KASINICS (KASI Near InfraredCamera System) attached to the BOAO (Bohyun-san Optical Astronomy Observatory) 1.8-m reector inYoungcheon, South Korea and examined photometric variations on the two time scales. So far we have notfound any periodic brightness variations on the scale of a night. On the other hand, we have found thatthere seems to be a periodic brightness variation with a period of approximately 45 days. In addition,high-resolution optical spectroscopic observations of V582 Aur were performed from February 2013 toMay 2014 with the high-resolution echelle spectrograph BOES attached to the BOAO 1.8-m reector.We analyzed several spectral lines to understand the physical state of V582 Aur. The P Cyg pro les areclearly shown in the H line and Na I D line.Key words: Pre-main sequence variables: FU Orionis type object: Periodic brightness variation: PCyg pro le1. INTRODUCTIONV582 Aur, which is located in an active star formationregion near the Auriga OB2 association, is a new FUorobject candidate. The increase in brightness of this ob-ject began in late 1984 or early 1985 and it reached amaximum brightness in January 1986. After the max-imum light, the brightness of this star has remained ina state of maximum brightness. The light variation ofV582 Aur was rst reported by Anton Khruslov (Samus,2009) and it was con rmed as an FUor object by Semkovet al. (2011; 2013). An FUor object is a low-mass pre-main sequence star de ned by Herbig (1977). FUors gothrough an outburst with an amplitude of V ˇ 4{6mag. They are located in star forming regions and areassociated with reection nebula. In addition, they showthe spectra of F-G supergiants during the outburst, astrong Li I 6707A absorption line, and near-infrared COband (Herbig, 1977; Reipurth & Aspin, 2010). One ofthe most important spectroscopic features of FUors isthe P Cyg pro le, which is commonly displayed in theNa I D and H lines, occurring due to strong winds fromthe center of star. Some FUors were found to exhibitperiodic spectroscopic (Herbig et al., 2003; Powell et