Projeto Observacional para 2007B - SO2007B-015

Autor: Raymundo Baptista
Instituição: UFSC
e-mail: bap@astro.ufsc.br

Co-autores:
Tiago Ribeiro de Souza

Título: Binary Parameters of Southern Pre-Cataclysmic Binaries - II

Resumo: We intend to obtain indirect imaging of fast-rotating late-type stars in order to study their chromospheric activity. This will allow us to perform an observational test of the explanation for the dearth of CVs in the range Porb=2-3 hr (the period gap). In this preparatory project we will use Osiris to obtain JHKs time-series of differential photometry over one orbit of a sample of southern Pre-CV binaries in order to derive the binary inclination, mass ratio and orbital separation, the masses of the two component stars, plus the spectral type, irradiation effects and fraction of Roche lobe filling of the late-type star and, when data allows, estimate the distance to the binary. Once the binary parameters are well known, it will be possible to apply indirect imaging techniques to high-resolution IR spectroscopy of the same sample of pre-CVs to reach the main aim of the project. As a bonus, we will increase the number of pre-CVs with well determined binary parameters by a factor of 4.