Can White Dwarfs in Intermediate Polars be Unveiled?
Résumé
The properties of white dwarf primaries in Intermediate Polars are mostly unknown because they almost never undergo low accretion states which can reveal the stellar components. V 709 Cas (Bonnet-Bidaud et al. 2001) and RX J1548-45 (Haberl et al. 2002) are the only two IPs known so far to show a peculiar optical spectrum, with broad absorption features around Balmer emissions but not around He lines, suggesting an origin in the white dwarf atmosphere. New optical observations and UV data of these systems make the white dwarf identification uncertain and leave the origin of the absorption features still controversial.