Investigation of the Outburst Activity of the Black Hole Candidate GRS 1739-278

Abstract

We have performed a joint spectral and timing analysis of the outburst of GRS 1739-278 in 2014 based on Swift and INTEGRAL data. We show that during this outburst the system exhibited both intermediate states: hard and soft. Peaks of quasi-periodic oscillations (QPOs) in the frequency range 0.1-5 Hz classified as type-C QPOs have been detected from the system. Using Swift/BAT data we show that after the 2014 outburst the system passed to the regime of mini-outburst activity: apart from the three mini-outbursts mentioned in the literature, we have detected four more mini-outbursts with a comparable (~20 mCrab) flux in the hard energy band (15-50 keV). We have investigated the influence of the accretion history on the outburst characteristics: the dependence of the peak flux in the hard energy band in the low/hard state on the time interval between the current and previous peaks has been found (for the outbursts during which the system passed to the high/soft state).

19 pages, 10 figures

References in corpus (7)

• X-ray Properties of Black-Hole Binaries
• An online repository of Swift/XRT light curves of GRBs
• Spectral and Fourier analyses of X-ray QPO in accreting black holes
• New Constraints on the Black Hole Low/Hard State Inner Accretion Flow with NuSTAR
• Detection of X-ray spectral state transitions in mini-outbursts of black hole transient GRS 1739-278
• The outburst of the X-ray nova GRS 1739-278 in September, 2016
• INTEGRAL and Swift observations of the hard X-ray transient MAXI J1828-249

Cited by in corpus (1)

• A NICER look at the state transitions of the black hole candidate MAXI J1535-571 during its reflares