Gas flow in close binary star systems
نویسندگان
چکیده
An accretion disc around a compact star in a close binary star system is an ubiquitous and essential object. Accretion discs play, for example, important roles in cataclysmic variables, nova and X-ray sources. The standard theory to explain the physics in accretion discs is the α-disc model proposed by Shakura and Sunyaev (1973). In this theory, the accretion disc is in some kind of turbulent state, in which turbulent viscosity is parameterized by a phenomenological parameter α. However, the α-disc model is rather crude approximation to an accretion disc in a close binary system: tidal effects due to the companion star are, for example, not taken into account. To better take these effects into account, one has to rely on numerical simulations.
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