The Energy Dependence of the Aperiodic Variability for Cygnus X-1, GX 339-4, GRS 1758-258, & 1E 1740.7-2942

Abstract

Using the data from the Rossi X-ray Timing Explorer (RXTE), we report the different energy dependence of the variability of the four persistent hard X-ray sources in the low-hard state: Cygnus X-1, GX 339-4, GRS 1758-258 and 1E 1740.7-2942. Cygnus X-1 is found to have a flatter power density spectrum (PDS) shape at higher energies. The other three sources have energy independent PDS shapes. The energy dependence of the overall variability (the integrated rms amplitude) varies from source to source and from observation to observation. 1E~1740.7-2942, for example, has a variability generally increasing with energy while GX 339-4 has a decreasing variability. A general trend is found in the four sources that the integrated rms amplitude anti-correlates with the X-ray flux. We compare these distinct energy dependent behaviors with several emission models. None of the models can fully explain all the features that we have found.

18 pages, 6 figures. Accepted for publication in ApJ

References in corpus (13)

• Advection-Dominated Accretion: A Self-Similar Solution
• Advection-Dominated Accretion and the Spectral States of Black Hole X-Ray Binaries: Application to Nova Muscae 1991
• RXTE Observation of Cygnus X-1: II. Timing Analysis
• Spectral evolution of magnetic flares and time lags in accreting black hole sources
• Unified Description of Accretion Flows Around Black Holes
• Temporal Properties of Cygnus X-1 During the Spectral Transitions
• The EXOSAT data on GX 339-4: further evidence for an ``intermediate'' state
• X-Ray Fluctuations from Locally Unstable Advection-Dominated Disks
• A New Model for the Hard Time Lags in Black Hole X-Ray Binaries
• A New Equilibrium for Accretion Disks Around Black Holes
• Long-Term X-ray Monitoring of 1E 1740.7-2942 and GRS 1758-258
• Comptonization signatures in the rapid aperiodic variability of Galactic black-hole candidates
• Multiwavelength Observations of GX 339-4 in 1996. II. Rapid X-ray Variability

Cited by in corpus (25)

• Understanding the long-term spectral variability of Cygnus X-1 with BATSE and ASM observations
• X-ray continuum variability of MCG-6-30-15
• Patterns of energy-dependent variability from Comptonization
• Black hole masses from power density spectra: determinations and consequences
• X-ray and gamma-ray spectra and variability of the black-hole candidate GX 339-4
• The energy dependence of the centroid frequency and phase lag of the QPOs in GRS 1915+105
• The high frequency power spectrum of Markarian 766
• The Energy-dependent X-ray Timing Characteristics of the Narrow Line Seyfert 1 Mkn 766
• Spectra and time variability of galactic black-hole X-ray sources in the low/hard state
• Discovery of powerful millisecond flares from Cygnus X-1
• Higher Order Variability Properties of Accreting Black Holes
• X-ray Variability Characteristics of the Seyfert 1 Galaxy NGC 3783
• NuSTAR and INTEGRAL observations of a low/hard state of 1E1740.7-2942
• Correlated optical/X-ray variability in the high-mass X-ray binary SAX J2103.5+4545
• Simultaneous Observations of GRS 1758-258 in 1997 by VLA, IRAM, SEST, RXTE and OSSE: Spectroscopy and Timing
• Energy-dependent variability from accretion flows
• Long-term Multi-wavelength Observations of GRS 1758-258 and the ADAF Model
• Hard X-ray/Soft gamma-ray experiments and missions: overview and prospects
• Coronal cooling and its signatures in the rapid aperiodic variability of Galactic black-hole candidates
• Determination of QPO properties in the presence of strong broad-band noise: a case study on the data of MAXI J1820+070
• Peculiar Extended X-ray Emission around the "Radio-Loud" Black Hole Candidate 1E1740.7-2942
• Fast Timing Analysis of Cygnus X-1 using SPI on board INTEGRAL
• Broadband X-ray properties of black holes GRS 1758-258 and 1E 1740.7-2942: AstroSat and NuSTAR results
• XMM-Newton view of a hard X-ray transient IGR J17497-2821
• Modeling of High-Frequency Variability in X-ray Binaries with Black Holes