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

Year 2018, Volume: 60 Issue: 2, 27 - 40, 01.08.2018

Doğuş Özuyar

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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