Photometric and Spectroscopic Studies of BW Eri

Abstract

New CCD photometric and spectroscopic studies of eclipsing binary BW Eridani are presented. BVRI photometric observations were carried out using Bosscha’s 20-cm (f/10) GAO-ITB Remote Telescope System in 2006 and 28-cm (f/10) Schmidt–Cassegrain telescope in 2007. Low-resolution spectra R = 400 ∼ 500 were obtained using Bosscha’s 45-cm (f/12) GOTO telescope equipped with Bosscha Compact Spectrograph (Malasan et al. 2001) in optical window. The investigation of B, V , R, I light curves by fitting method yields in temperature 7, 480 ± 2, 950 K and 5, 200 ± 875 K, fractional radii 0. 491 ± 0. 126 and 0. 280 ± 0. 135, for the primary and secondary components, respectively. An inclination 89^∘ ± 2. 2^∘ is also deduced. We obtained the time for primary eclipse at HJD = 2453769. 1760 ± 0. 0118 by Kwee–van Woerden method, which indicate period change. At the orbital phase of 0.955 and 0.511 the star’s spectrum is consistent with spectral type G8V for the secondary and A7V for the primary, respectively.