Spectral and accretion evolution of H1743−322 during outbursts in RXTE era

Abstract

Aims. We study the spectral evolution of the H1743−322 during outbursts in the RXTE era. We aim to connect the variation of the spectral parameters with the accretion parameters along with the progress of the outbursts. We understand the evolution of the accretion parameters and hence the dynamics of the accretion process in light of the irradiated disc instability model. Methods. We provide a comprehensive study of all the outbursts of H1743−322 between 2003 and 2011. We performed spectral modelling of all the RXTE/PCA observations using phenomenological models. Also, we carried out spectral modelling by a hydrodynamic accretion flow model and estimated the accretion parameters. We applied the irradiated disc instability scenario in the presence of both Keplerian and sub-Keplerain accretion components to understand the evolution of accretion parameters. For this purpose, we propose a toy model for the time variation of the accretion rates following a powerlaw during outbursts. Results. All of the outbursts show spectral state transitions in the hardness-intensity diagram. The 2003 and 2004 outbursts are long-duration outbursts and relatively softer than the other outbursts. The 2008b and 2011 outbursts provide a unique opportunity to estimate the critical accretion rate (ṁdc) for triggering an outburst in this system within a narrow range of 0.076 < ṁdc < 0.086 (in Eddington units). In the absence of any dynamical measurement, we attempt to constrain a few orbital parameters of the system using an assumed mass and ṁdc in the range.

On the origin of core radio emissions from black hole sources in the realm of relativistic shocked accretion flow

“…We further indicate that the shock induced global accretion solutions are potentially promising in explaining the spectral state transitions of BH-XRBs (Nandi et al 2018;Radhika et al 2018;Aneesha, Mandal, & Sreehari 2019;Baby et al 2020;Aneesha & Mandal 2020), when the two-component accretion flow configuration is espoused (Chakrabarti & Titarchuk 1995;Smith et al 2001;Smith, Heindl, & Swank 2002;Mandal & Chakrabarti 2007;Iyer, Nandi, & Mandal 2015). With this, we further infer that the shock transition radius perhaps be visualized as the inner edge of the truncated disc (Esin, McClintock, & Narayan 1997;Done, Gierliński, & Kubota 2007;Kylafis et al 2012).…”

Accretion Scenario of MAXI J1820+070 during 2018 Outbursts with Multi-mission Observations

“…Since the accretion happens at the viscous timescale, the outside-in trigger will have a longer rise time (∼ 50 − 100 days) whereas inside-out trigger produces an outburst of shorter rise time (∼ 10 − 20 days). Most of the outbursts of GX 339-4 are examples of the former category (Aneesha et al 2019) whereas that of GRO J1655-40 and H1743-322 belong to the second class (Aneesha & Mandal 2020) of outbursts.…”

“…Transient sources spend most of their time in quiescent state, having a very low luminosity and a non-thermal hard spectrum. The nature of outburst varies between the BH systems; even different outbursts of the same system show different evolution trends (Aneesha et al 2019;Aneesha & Mandal 2020). However, the behavior of the outbursts in a hardness-intensity diagram (HID), which is a plot of the X-ray intensity versus hardness ratio (HR), shows some general regulations (Homan et al 2001;Fender et al 2004;Remillard & McClintock 2006;Nandi et al 2012;Motta et al 2012;Radhika & Nandi 2014).…”

Review the possible advective disk structures around a black hole with two-type gas inflows

“…The radial interface situation between the non-advective KD and the shocked flow has already been studied for the modeling of the spectral states of the BHs by many authors (Chakrabarti & Titarchuk 1995;Mandal & Chakrabarti 2010;Nandi et al 2012;Aneesha & Mandal 2020;Baby et al 2020;Palit et al 2020, and references therein). As we have discussed that the accreted matter can have hot-mode and cold-mode gases on the AB, so on the basis of theoretical solutions, the accreting matter can form various kind of the flows.…”