Anticorrelated Hard/Soft X-Ray Emission from the X-Ray Burster 4U 0614+091

Abstract

We have detected transient X-ray activity from the X-ray burster 4U~0614+091 simultaneously with BATSE/CGRO (20-100 keV) and ASM/RXTE (1-12 keV). The peak fluxes reach approximately 40 mCrab in both instruments over a period of about 20 days. The variable emission shows a clear anticorrelation of the hard X-ray flux with the soft X-ray count rate. The observed anticorrelation is another clear counterexample to the notion that only black hole binaries exhibit such correlations. The individual spectra during this period can be fit by power laws with photon indices 2.2+-0.3 (ASM) and 2.7+-0.4 (BATSE), while the combined spectra can be described by a single power law with index 2.09+-0.08. BATSE and the ASM/RXTE are a good combination for monitoring X-ray sources over a wide energy band.

to appear ApJL vol 469, 20 Sept 1996

References in corpus (2)

• First Results from the All-Sky Monitor on the Rossi X-ray Timing Explorer
• Correlation Between BATSE Hard X-ray Spectral and Timing Properties of Cygnus X-1

Cited by in corpus (9)

• Mechanisms for High-frequency QPOs in Neutron Star and Black Hole Binaries
• Relations Between Timing Features and Colors in the X-Ray Binary 4U 0614+09
• Optical spectra of the carbon-oxygen accretion discs in the ultra-compact X-ray binaries 4U 0614+09, 4U 1543-624 and 2S 0918-549
• The INTEGRAL Galactic bulge monitoring program: the first 1.5 years
• What ignites on the neutron star of 4U 0614+091?
• Simultaneous Measurements of X-Ray Luminosity and Kilohertz Quasi-Periodic Oscillations in Low-Mass X-Ray Binaries
• Evidence from quasi-periodic oscillations for a millisecond pulsar in the low mass x-ray binary 4U 0614+091
• Disappearance of Hard X-ray Emission in the Last BeppoSAX Observation of the Z Source GX 349+2
• A comprehensive approach to analyzing the XMM-Newton data of Seyfert 1 galaxies