Estimation of Mass of Compact Object in H 1743-322 From 2010 and 2011 Outbursts Using Tcaf Solution and Spectral Index–qpo Frequency Correlation

Abstract

The well known black hole candidate H 1743-322 exhibited temporal and spectral variabilities during several outbursts. Daily variation of the accretion rates and the flow geometry change on a daily basis during each of the outbursts could be understood very well using the recent implementation of two component advective flow (TCAF) solution of the viscous transonic flow equations as an additive table model in XSPEC. This has dramatically improved our understanding about the accretion flow dynamics. Most interestingly, the solution allows to treat mass of the black hole candidate as a free parameter and there mass could be estimated from spectral fits. In this paper, we fit the data of two successive outbursts of H 1743-322 in 2010 and 2011 and studied evolutions of accretion flow parameters, such as, two component (Keplerian and sub-Keplerian) accretion rates, shock location (i.e., size of the Compton cloud), etc. We assume that the model Normalization remains the same accross the states in both these outbursts. We use this to estimate mass of the black hole and found that it comes out in the range of 9.25 − 12.86M ⊙ . For the sake of comparison, we also estimated mass using Photon index vs. QPO frequency correlation method which turns out to be 11.65 ± 0.67M ⊙ using GRO J1655-40 as reference source. Combining these two estimates, the most probable mass of the compact object becomes 11.21 +1.65 −1.96 M ⊙ .

Delayed outburst of H 1743–322 in 2003 and relation with its other outbursts

“…During our analysis, we found that the 2003 and part of 2004 (see also Bhattacharjee et al 2017) outbursts are very unsettling in the sense that either the model fitted parameters fluctuate on a daily basis as in the phenomenological diskbb plus power-law model or it is impossible to fit the data with TCAF which satisfactorily fitted other outbursts Molla et al 2017). Thus the disc structure is clearly non-steady and evolving.…”

“…For the analysis, HeaSOFT package version 6.19 was used with XSPEC 12.9.0 (Arnaud 1996). We use TCAF model (local model with fits file TCAF v0.3.fits) following methods explained in greater details by Debnath et al (2014Debnath et al ( , 2015a; Mondal et al (2014Mondal et al ( , 2016; Molla et al (2016Molla et al ( , 2017; Jana et al (2016); Chatterjee et al (2016); Bhattacharjee et al (2017) to obtain fits of the spectra along with tbabs (Wilms et al 2000) to account for interstellar extinction. We take the fixed value of hydrogen column density at N H = 1.6 × 10 22 atoms cm −2 (Capitanio et al 2009).…”

“…Shaposhnikov & Titarchuk (2009) with the use of another reference mass estimated its mass at 13.3 ± 3.2M ⊙ using their spectral index -QPO frequency correlation method. Recently, Molla et al (2017) estimated its mass to be 11.21 +1.65 −1.96 M ⊙ based on timing and spectral properties of 2010 and 2011 outbursts. Bhattacharjee et al (2017) used the Two component Accretion Flow (TCAF) model to fit data of 2004 outburst and estimated the mass to be in the same range.…”

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

“…Tursunov & Kološ (2018) found the mass (M) to be 11.2 M and spin to be 0.4 from the magnetic relativistic precession model to explain the twin high-frequency QPOs and low-frequency QPO. By fitting the spectrum using the two-component advective flow model and the spectral index versus QPO correlation, Molla et al (2017) estimated the mass of the compact object to be 11.21 +1.65 −1.96 M . Whereas Bhattacharjee et al (2017) constrained the mass of the black hole in the range of 10.31 M −14.07 M from spectral modelling and the evolution of the QPO frequency.…”

Alignment and precession of a black hole misaligned with its accretion disc: application to low-mass X-ray binaries

“…This black hole LMXB has undergone six outbursts since 2003 with the soft disc dominated state (considering up to 2015 May; Tetarenko et al (2016)), which we use for calculating the duty cycle (which is roughly ∼ 0.07). The mass of this black hole was determined to be 13.3 ± 3.2 M ⊙ by Shaposhnikov & Titarchuk (2007) Molla et al (2017) using 2010 and 2011 RXTE/PCA outburst data. But the mass of the secondary companion star is not known for this transient system.…”