Properties of the propagating shock wave in the accretion flow around GX 339-4 in the 2010 outburst

Abstract

Context. The black hole candidate GX 339-4 exhibited an X-ray outburst in January 2010, which is still continuing. We here discuss the timing and the spectral properties of the outburst using RXTE data. Aims. Our goal is to study the timing and spectral properties of GX 339-4 using its recent outburst data and extract information about the nature of the accretion flow. Methods. We use RXTE archival data of the recent GX 339-4 outburst and analyze them with the NASA HEAsoft package, version 6.8. We then compare the observed quasi-periodic oscillation (QPO) frequencies with those from existing shock oscillation model and obtain the nature of evolution of the shock locations during the outburst. Results. We found that the QPO frequencies are monotonically increasing from 0.102 Hz to 5.69 Hz within a period of ∼26 days. We explain this evolution with the propagating oscillatory shock (POS) solution and find the variation of the initial and final shock locations and strengths. The model fits also give the velocity of the propagating shock wave, which is responsible for the generation of QPOs and their evolutions, at ∼10 m s −1 . We observe from the spectra that up to 2010 April 10, the object was in a hard state. After that, it went to the hard-intermediate state. On April 18, it had a state transition and went to the soft-intermediate state. On May 15, another state transition was observed and the source moved to the soft state. Conclusions. As in the previously fitted outburst sources, this source also showed the tendency of a rapidly increasing QPO frequency (ν QPO ) on a viscous time scale, which can be modeled quite accurately. In this case, the shock seems to have disappeared at about ∼172 Schwarzschild radii, unlike in the 2005 outburst of GRO J1655-40, where the shock disappeared behind the horizon.

Accretion flow dynamics of a few transient black hole candidates from their spectral evolution study using TCAF solution

“…The uncertainty in the normalization is reflected in the uncertainly in the mass. This allows us to predict the most probable range of the mass of unknown BHC, which could also be verified from POS model 2,[16][17][18] fitted QPO frequency evolutions during rising and declining phases of the outbursts and other independent ways.…”

Multi-resonance orbital model of high-frequency quasi-periodic oscillations: possible high-precision determination of black hole and neutron star spin

“…In all of these models the frequency difference ν U − ν L decreases with increase in the magnitude of the lower and upper frequencies in accord with trends given by the observational data Belloni et al 2007a;Boutelier et al 2010). An alternative explanation of HF QPOs in neutron star systems provides the sonic-point and spin-resonance models (Lamb & Miller 2001, higher-order nonlinearity model (Mukhopadhyay 2009), shock-wave model Debnath et al 2010), Rayleigh-Taylor gravity wave model (Osherovich & Titarchuk 1999;Titarchuk 2003;Titarchuk & Shaposhnikov 2008), MHD Alfvén wave oscillation model (Zhang 2004;Zhang et al 2006Zhang et al , 2007Shi 2011), and MHD model (Shi & Li 2009). …”

Temporal and spectral properties of MAXI J1659-152 during its 2010 outburst

“…The paper is organized in the following way: in the next Section, we briefly discuss observation and data analysis procedures using HEASARCs HeaSoft software package. In §3, we present results of timing and spectral analysis using propagating oscillatory shock (POS) model (13,14,15,2,3) and TCAF fits file, and discuss the variation of different flow parameters extracted from model fits and compare POS and TCAF model fitted results. Finally in §4, we present a brief discussion and make our concluding remarks.…”