PHOTOMETRIC AND SPECTROSCOPIC VARIABILITY OF A POSSIBLE β CEPHEI STAR; V960 TAU

Abstract

In this study, high-precision photometric data of V960 Tau are presented in order to reveal the pulsation characteristics of the star. The data are taken from the HI-1A instrument of the STEREO satellite between 2007 and 2011. The results of the photometric analysis are compared with findings derived from spectroscopic line measurements (equivalent width and line intensity) to have a better understanding of the relation between light curve variabilities and circumstellar disk structure. As a result of the photometric and spectroscopic analyses, it is seen that frequency distribution and amplitude intensities of the star are the same with those of a typical Be star. The star has at least 14 independent frequencies and most of these are accumulated around the peaks at 1.01 and 1.95 c/d. With this configuration, the star exhibits 2:1 frequency distribution. Even though the frequency distribution is quite similar to a Slowly Pulsating B type star, V960 Tau may be considered as a β Cephei type variable based on its temperature and luminosity values. Additionally, the equivalent width and line intensity values of the emission lines appear to be correlated with the light curve variations. This may be an indication that the photometric variations may be related to the environmental disc structure.

Keywords

• V960 Tau,β Cephei variables,Emission line,Be stars,Data analysis,STEREO satellite

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