Lilia Ferrario , Jianke Li , Curtis Saxton , Kinwah Wu, PASA, 16 (3), 234.
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Title/Abstract Page: Accretion Processes in Magnetic
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Introduction
In the magnetic Cataclysmic Variables (mCVs), the accreting white dwarf has a strong enough magnetic field (1-250 MG) to channel material along field lines, either directly from the accretion stream (AM Hers and some Intermediate Polars (IPs)) or from the inner regions of a truncated accretion disc (disc fed IPs and DQ Hers). In the mCVs, the gas in the resulting field chanelled flow (the accretion curtains or funnel) is heated by radiation from shocks at the white dwarf surface and produces continua and emission lines which have a significant impact on the observed properties of these systems.This paper summarises the results of some aspects of the accretion phenomena occurring in mCVs which were presented in November 1998 at the ANU Astrophysical Theory Centre workshop on "Magnetic Fields and Accretion". The theoretical modelling of the optical line spectrum and X-ray light curves, requires a proper physical treatment of the accretion flow and in this workshop we have seen some of these important problems addressed.
The range of topics covered varied from the theoretical interpretation of the so-called ``magnetic levitation'' which gives an explanation, in terms of ideal MHD, of the reason why material escaping from the secondary star via the inner Lagrangian point becomes threaded by magnetic field lines and is channelled by the super-strong primary's magnetic field towards the stellar surface (see section 1). The subsequent paper, presented in section 2, dealt with the radiation properties of the material forming the accretion funnel, allowing for a full 3-D radiation transfer treatment to reproduce the observed optical spectra. Finally, we present in sections 3 and 4 two papers concerning some of the fundamental properties of the accretion shock at the base of the accretion funnel where the material finally settles on to the white dwarf surface and cools down via thermal bremsstrhalung and cyclotron radiation.
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Title/Abstract Page: Accretion Processes in Magnetic
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