SW Sextantis in an excited, low state

¹ Astronomical Institute "Anton Pannekoek"/CHEAF, Kruislaan 403, 1098 SJ, Amsterdam, The Netherlands
² Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
³ Isaac Newton Group of Telescopes, Apartado de Correos 321, 38700, Sta Cruz de La Palma, Islas Canarias, Spain
⁴ Physics Department, UAH, Huntsville, AL 35899, USA

Corresponding author: P. J. Groot, pgroot@cfa.harvard.edu

Received: 24 August 1999
Accepted: 5 December 2000

Abstract

We present low-resolution spectrophotometric optical observations of the eclipsing nova-like cataclysmic variable SW Sex, the prototype of the SW Sex stars. We observed the system when it was in an unusual low state. The spectrum is characterized by the presence of strong Heii and Civ emission lines as well as the normal single peaked Balmer emission lines. The radial temperature profile of the disk follows the expected only in the outer parts and flattens off inside 0.5 times the white dwarf Roche lobe radius. The single peaked emission lines originate in a region above the plane of the disk, at the position of the hot spot.