All of these previous works are only valid for the accretion of a single star because of their implementation of the Newtonian gravitational potential. Our analytical study is carried out under the assumption of self-similarity, which was first proposed by Spruit ( 1987) and adopted in subsequent works (Vishniac & Diamond 1989 Larson 1990 Chakrabarti 1990a Hennebelle et al. In this paper, we perform an analytical study of non-axisymmetric and stationary solutions with spiral shocks for the accretion disk in an interacting binary system composed of a compact star and a normal star. 2019 Baptista & Wojcikiewicz 2020 Lee et al. 1997 Neustroev & Borisov 1998 Pala et al. Simultaneously, observations also confirm the presence of spiral structure and spiral shocks in the accretion disk (Steeghs et al. A spiral shock is easily produced due to disk instabilities or tidal perturbations in the non-axisymmetric flow, even in the inviscid flow, which has been confirmed by various simulation studies (Sawada et al. 1987 Chakrabarti 1990a Livio & Spruit 1991 Lanzafame et al. 2015, 2017, 2019).īy contrast, the spiral-shock model was first proposed as an effective angular momentum transfer mechanism by Michel ( 1984) and gradually improved in a series of subsequent works (Sawada et al. Mass ejection (jets or outflows from disks) due to shock compression has also been extensively investigated with this model in recent years (Chattopadhyay & Das 2007 Das & Chattopadhyay 2008 Kumar & Chattopadhyay 2013 Aktar et al. This model has been used to explain the observational spectral states and quasi-periodic oscillations of compact objects (Chakrabarti & Titarchuk 1995 Molteni et al. 1999 Becker & Kazanas 2001 Chakrabarti & Das 2004 Fukumura & Tsuruta 2004 Sarkar & Das 2016 Dihingia et al. A series of theoretical works proposed and gradually improved the radially standing shock model (Fukue 1987 Chakrabarti 1989 Lu et al. These pioneering works are cited in many follow-up studies and constitute the prevailing accretion–ejection theory.Īs a useful supplement to the prevailing theory, the shocks in accretion flow, including axisymmetric, radially standing shocks and non-axisymmetric spiral shocks, have been rigorously investigated in the literature over the past few decades. However, Blandford & Payne ( 1982) proposed a wind-originating mechanism through a large-scale open magnetic field emerging from the disk. Blandford & Znajek ( 1977) proposed a purely electromagnetic energy extraction mechanism from a black hole to boost a jet. This model assumes that viscosity originates from turbulence, which can be excited through magneto-rotational instability of a small-scale tangle magnetic field (Balbus & Hawley 1991). In this regard, Shakura & Sunyaev ( 1973) first proposed the " α-disk" model. A fundamental issue is that the transfer of angular momentum and mass has been a concern of many studies in the past few decades (Pringle 1981). The accretion–ejection process is one of the most powerful phenomena in the universe and is ubiquitously observed around protostars, white dwarfs (WDs), neutron stars, and black holes.
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