Swift and RXTE observations of the black hole transient GX 339-4 in the hard state between outbursts

Abstract

We use simultaneous Swift and RXTE observations of the black hole binary GX 339-4 to measure the inner radius of its accretion disk in the hard state down to 0.4% L_{Edd} via modeling of the thermal disk emission and the relativistically broadened iron line. For the luminosity range covered in this work, our results rule out a significantly truncated disk at 100-1000 R_g as predicted by the advection-dominated accretion flow paradigm. The measurements depend strongly on the assumed emission geometry, with most results providing no clear picture of radius evolution. If the inclination is constrained to roughly 20 degrees, however, the measurements based on the thermal disk emission suggest a mildly receding disk at a luminosity of 0.4% L_{Edd}. The iron abundance varies between roughly 1-2 solar abundances, with the i=20 degrees results indicating a negative correlation with luminosity, though this is likely due to a change in disk illumination geometry.

24 pages, 7 figures, Accepted for publication in the Astrophysical Journal

References in corpus (5)

• X-ray Properties of Black-Hole Binaries
• A Long, Hard Look at the Low-Hard State in Accreting Black Holes
• A systematic look at the Very High and Low/Hard state of GX 339-4: Constraining the black hole spin with a new reflection model
• A Prominent Accretion Disk in the Low-Hard State of the Black Hole Candidate SWIFT J1753.5-0127
• Broadband X-ray Spectra of GX 339-4 and the Geometry of Accreting Black Holes in the Hard State

Cited by in corpus (10)

• X-ray Reflection Spectroscopy of the Black Hole GX 339-4: Exploring the Hard State with Unprecedented Sensitivity
• The complex accretion geometry of GX 339-4 as seen by NuSTAR and Swift
• Complete Multiwavelength Evolution of Galactic Black Hole Transients During Outburst Decay I: Conditions for "Compact" Jet Formation
• Spectral analysis of the XMM-Newton data of GX 339-4 in the low/hard state: disc truncation and reflection
• Characterization of GX 339-4 outburst of 2010-11: analysis by xspec using two component advective flow model
• The relation between radio and X-ray luminosity of black hole binaries: affected by inner cool disks?
• NuSTAR and XMM-Newton observations of the 2015 outburst decay of GX 339-4
• Spectro-timing study of GX 339-4 in a hard intermediate state
• GRS 1739-278 observed at very low luminosity with XMM-Newton and NuSTAR
• A magnetic model for low/hard state of black hole binaries