Re-interpreting the GRS 1915+105 observations within the variable TADAF scenario

Abstract

The Galactic microquasar GRS 1915+105 is one of the most interesting X-ray binary systems, exhibiting an exceptionally diverse range of observational phenomena. It displays the most complicated and variable X-ray light curves and carries superluminal radio jets. Its X-ray and radio fluxes change on very different timescales, from seconds to minutes to days and even longer. In recent years, its jet has also displayed large position angle shifts. We find that most of the observational phenomena can be well explained within our newly developed variable turbulent ADAF (TADAF) model. The accretion disk is composed of an outer thin disk and an unstable inner TADAF torus whose size is variable. The previously suggested 'disappearance' and regain of the inner disk is understood as the transition between the thick TADAF and the thin disk. Some types of QSOs are understood in terms of the radius change of the TADAF torus. The jet position angle shift is understood as the direct sideways frame-dragging on the jet by the Lense-Thirring effect from a tilted, spinning black hole. The slower the outshooting jet, the larger the angle shift. We note that such an effect also applies to other sources, such as V404 Cygni and the AGN M87. This mechanism may also be applicable to the famous 'precessing' jet in SS 433.