Intermediate Polars (IPs) are the most intriguing systems among Cataclysmic Variables (CVs), as the X-ray spectral and temporal behaviour is not similar in all members. The simultaneous study of broad-band X-ray temporal and spectral properties is crucial to characterize the accretion geometry and the physical conditions of the accretion flow onto moderately (B<10-20 MG) magnetized white dwarfs. Thanks to the wide energy coverage, BeppoSAX observations of bright IPs have allowed to infer the accretion mode, the presence of complex patchy absorption in the pre-shock flow and of a Compton reflection component from the white dwarf surface as well as to measure simultaneously the temperature of the post-shock region and that of the irradiated poles of the white dwarf atmosphere. The observations show that accretion in these systems cannot be reconciled with a single scenario, accounting for their soft and hard X-ray behaviour. Many known systems and IP candidates still lack of X-ray characterization in both soft and hard bands, for which current X-ray missions are providing new and unprecedented results.
de Martino D, Matt G, Belloni T, Chiappetti L, Haberl F, & Mukai K (2004). The X-ray emission of Intermediate Polars: the BeppoSAX view and the role of current missions. NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS, 132, 693-696 [10.1016/j.nuclphysbps.2004.04.123].
The X-ray emission of Intermediate Polars: the BeppoSAX view and the role of current missions
MATT, Giorgio;
2004
Abstract
Intermediate Polars (IPs) are the most intriguing systems among Cataclysmic Variables (CVs), as the X-ray spectral and temporal behaviour is not similar in all members. The simultaneous study of broad-band X-ray temporal and spectral properties is crucial to characterize the accretion geometry and the physical conditions of the accretion flow onto moderately (B<10-20 MG) magnetized white dwarfs. Thanks to the wide energy coverage, BeppoSAX observations of bright IPs have allowed to infer the accretion mode, the presence of complex patchy absorption in the pre-shock flow and of a Compton reflection component from the white dwarf surface as well as to measure simultaneously the temperature of the post-shock region and that of the irradiated poles of the white dwarf atmosphere. The observations show that accretion in these systems cannot be reconciled with a single scenario, accounting for their soft and hard X-ray behaviour. Many known systems and IP candidates still lack of X-ray characterization in both soft and hard bands, for which current X-ray missions are providing new and unprecedented results.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
