Spectroscopy and photometry of the pre-cataclysmic binary PG1026+002⁽¹⁾

Albert Bruch (1) - Marcos P. Diaz (2)

(1) Laboratório Nacional de Astrofísica, CP 21, BR-37500-000 Itajubá - MG, Brazil
(2) Instituto Astronômico e Geofísico, Universidade de São Paulo, CP 3386, BR-01060-970 São Paulo - SP, Brazil

Abstract:

Time resolved spectroscopic and photometric observations of the pre-cataclysmic binary PG1026+002 are presented. An improved orbital period is derived from radial velocity measurements of the Halpha emission component. The phasing of the variations of the equivalent width of this line confirms the suspicion expressed by [Saffer et al. (1993)] that the emission is intrinsic to the red dwarf and not due to a reflection effect as observed in several other pre-cataclysmic binaries. The very slight variations in the light curve detected in our photometric observations can, however, excellently be modeled as being caused by illumination of the secondary by the primary white dwarf.

Stars: variables: other - Stars: individual: PG1026+002