EDP Sciences
Free access
Volume 372, Number 2, June III 2001
Page(s) 557 - 562
Section Formation, structure and evolution of stars
DOI http://dx.doi.org/10.1051/0004-6361:20010522

A&A 372, 557-562 (2001)
DOI: 10.1051/0004-6361:20010522

A model for the optical high state light curve of AM Herculis

B. T. Gänsicke1, A. Fischer1, R. Silvotti2 and D. de Martino2

1  Universitäts-Sternwarte Göttingen, Geismarlandstr. 11, 37083 Göttingen, Germany
2  Osservatorio di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy
    e-mail: demartin@na.astro.it, silvotti@na.astro.it

(Received 28 June 2000 / Accepted 4 April 2001)

We present a simple quantitative model that can describe the photometric B and V band light curves of AM Herculis obtained during a high state. The double-humped shape of the V band light curve is dominated by cyclotron emission from a region at the main accreting pole with an area of ~ $5\times10^{16} \mathrm{cm^2}$ and sustaining an inflow of ~0.06 $\rm g cm^{-2} s^{-1}$. The almost unmodulated B band is dominated by emission from the accretion stream. The contribution of the heated white dwarf to the optical emission is small in the B band, but comparable to that of the accretion stream in the V band. The emission of the secondary star is negligible both in B and in V.

Key words: accretion -- novae, cataclysmic variables -- stars: binaries close -- stars: individual: AM Her -- stars: white dwarfs

Offprint request: B. Gänsicke, boris@uni-sw.gwdg.de

SIMBAD Objects

© ESO 2001