Ejection of the inner accretion disk in GRS 1915+105: the magnetic rubber-band effect

Nandi, A. ; Chakrabarti, S. K. ; Vadawale, S. V. ; Rao, A. R. (2001) Ejection of the inner accretion disk in GRS 1915+105: the magnetic rubber-band effect Astronomy and Astrophysics, 380 (1). pp. 245-250. ISSN 0004-6361

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Official URL: http://www.aanda.org/index.php?option=com_article&...

Related URL: http://dx.doi.org/10.1051/0004-6361:20011444

Abstract

We examine theoretically the behaviour of the inner accretion disk in GRS 1915+105 when soft X-ray dips are present in the X-ray light curve. We assume the presence of a radial shock in the accretion disk, as in some of the Two Component Advective Flow (TCAF) solutions. We discuss the behaviour of the flux tubes inside a TCAF (which we name Magnetized TCAF or MTCAF model for brevity) and compare various competing forces on the flux tubes. In this MTCAF model, we find that the magnetic tension is the strongest force in a hot plasma of temperature ≳ 1010K and as a result, magnetic flux tubes entering in this region collapse catastrophically, thereby occasionally evacuating the inner disk. We postulate that this magnetic "rubber-band" effect induced evacuated disk matter produces the blobby components of outflows and IR/radio jets. We derive the size of the post-shock region by equating the time scale of the Quasi-Periodic Oscillations to the infall time of accreting matter in the post-shock region and found the shock location to be ∼ 45-66rg . We calculate the transition radius Ttr, where the Keplerian disk deviates into a sub-Keplerian flow, to be ∼ 320rg. Based on the derived X-ray spectral parameters, we calculate the mass of this region to be ∼ 1018g. We conclude that during the X-ray dips the matter in the post-shock region, which manifests itself as the thermal-Compton component in the X-ray spectrum, is ejected, along with some sub-Keplerian matter in the pre-shock region.

Item Type:Article
Source:Copyright of this article belongs to EDP Sciences.
Keywords:Accretion; Accretion Disks-Black Hole Physics-Stars; Winds; Outflows-Stars; Individual; GRS1915+105- X-rays; Stars
ID Code:85556
Deposited On:03 Mar 2012 14:50
Last Modified:19 May 2016 01:32

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