The power spectral properties of the Z-source GX 340+0

Abstract

We present an analysis of ~390 ksec of data of the Z source GX 340+0 taken during 24 observations with the Rossi X-ray Timing Explorer satellite. We report the discovery of a new broad component in the power spectra. The frequency of this component varied between 9 and 14 Hz, and remained close to half that of the horizontal branch quasi-periodic oscillations (HBO). Its rms amplitude was consistent with being constant around ~5%, while its FWHM increased with frequency from 7 to 18 Hz. If this sub-HBO component is the fundamental frequency, then the HBO and its second harmonic are the second and fourth harmonic component, while the third harmonic was not detected. This is similar to what was recently found for the black hole candidate XTE J1550-564. The profiles of both the horizontal- and the normal branch quasi-periodic oscillation peaks were asymmetric when they were strongest. We describe this in terms of a shoulder component at the high frequency side of the quasi-periodic oscillation peak, whose rms amplitudes were approximately constant at ~4% and \~3%, respectively. The peak separation between the twin kHz quasi-periodic oscillations was consistent with being constant at 339+-8 Hz but a trend similar to that seen in, e.g. Sco X-1 could not be excluded. We discuss our results within the framework of the various models which have been proposed for the kHz QPOs and low frequency peaks.

22 pages, including 10 figures and 3 tables, used emulateapj

References in corpus (4)

• The Complex Phase Lag Behavior of the 3-12 Hz Quasi-Periodic Oscillations during the Very High State of XTE J1550-564
• Kilohertz QPOs in Neutron Star Binaries modeled as Keplerian Oscillations in a Rotating Frame of Reference
• Timing Spectroscopy of Quasi-Periodic Oscillations in the Low-Mass X-ray Neutron Star Binaries
• The Timing Properties of Sco X-1 along its Z track as seen with EXOSAT

Cited by in corpus (60)

• Correlated X-ray Spectral and Timing Behavior of the Black Hole Candidate XTE J1550-564: A New Interpretation of Black Hole States
• The ABC of low-frequency quasi-periodic oscillations in Black-Hole Candidates: analogies with Z-sources
• Jets in neutron star X-ray binaries: a comparison with black holes
• Detecting gravitational wave emission from the known accreting neutron stars
• Boundary layer, accretion disk and X-ray variability in luminous LMXBs
• The atoll source states of 4U 1608-52
• XTE J1701-462 and its Implications for the Nature of Subclasses in Low-Magnetic-Field Neutron Star Low-Mass X-Ray Binaries
• RXTE observations of the neutron star low-mass X-ray binary GX 17+2: correlated X-ray spectral and timing behavior
• A Possible Explanation for the "Parallel Tracks" Phenomenon in Low-Mass X-Ray Binaries
• RXTE observations of the first transient Z source XTE J1701-462: shedding new light on mass accretion in luminous neutron star LMXBs
• The distribution of kHz QPO frequencies in bright LMXBs
• The Amplitude of the Kilohertz Quasi-periodic Oscillations in 4U 1728-34, 4U 1608-52, and Aql X-1, as a Function of X-ray Intensity
• Modelling the spin equilibrium of neutron stars in LMXBs without gravitational radiation
• Boundary layer emission and Z-track in the color-color diagram of luminous LMXBs
• Low and high frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1
• Simultaneous Measurements of X-Ray Luminosity and Kilohertz Quasi-Periodic Oscillations in Low-Mass X-Ray Binaries
• On the kHz QPO frequency correlations in bright neutron star X-ray binaries
• On the maximum amplitude and coherence of the kilohertz quasi-periodic oscillations in low-mass X-ray binaries
• Is there a link between the neutron-star spin and the frequency of the kilohertz quasi-periodic oscillations?
• The correlations between the twin kHz QPO frequencies of LMXBs
• Disk reflection signatures in the spectrum of the bright Z-source GX 340+0
• An explanation of the Z-track sources
• Why is it Difficult to Detect a Millisecond Pulsar in Neutron Star X-ray Binaries?
• The influence of spin on jet power in neutron star X-ray binaries
• Common Patterns in the Evolution between the Luminous Neutron Star Low-Mass X-ray Binary Subclasses
• The kilohertz quasi-periodic oscillations during the Z and atoll phases of the unique transient XTE J1701--462
• Simultaneous radio and X-ray observations of the low-mass X-ray binary GX 13+1
• Peculiar spectral and power spectral behaviour of the LMXB GX 13+1
• Low-frequency QPO from the 11 Hz accreting pulsar in Terzan 5: not frame dragging
• On the nature of the Cygnus X-2 like Z-track sources
• The correlations between the spin frequencies and kHz QPOs of Neutron Stars in LMXBs
• Timescale of twin-peak quasi-periodic oscillations and mass of accreting neutron stars
• B-field Determination from Magnetoacoustic Oscillations in kHz QPO Neutron Star Binaries: Theory and Observations
• A model for the Z-track phenomenon in GX 5-1 and observational evidence for the physical origins of the kHz QPO
• The X-ray fast-time variability of Sco X-2 (GX 349+2) with RXTE
• Stability of the photon indices in Z-source GX 340+0 for spectral states
• A connection between accretion states and the formation of ultra-relativistic outflows in a neutron star X-ray binary
• Canonical Timing and Spectral Behavior of LMC X-3 in the Low/Hard State
• Quasi-periodic oscillations and noise in neutron star and black-hole X-ray binaries
• The time derivative of the kilohertz quasi-periodic oscillations in 4U 1636-53
• Effects of Resonance in Quasiperiodic Oscillators of Neutron Star Binaries
• On the relativistic precession and oscillation frequencies of test particles around rapidly rotating compact stars
• AstroSat/LAXPC view of GX 17+2: Spectral Evolution along the Z-track
• High-frequency variability in neutron-star low-mass X-ray binaries
• Statistical properties of twin kHz QPO in neutron star LMXBs
• Coupled HBO and NBO variations in the Z source GX 5-1: inner accretion disk as the location of QPOs
• AstroSat view of the neutron star low-mass X-ray binary GX 340+0
• The properties of cross-correlation and spectra of the low-mass X-ray binary 4U 1608-52
• Simple analytic formula relating the mass and spin of accreting compact objects to their rapid X-ray variability
• Spectral and Timing evolution of GX 340+0 along its Z-track
• On one-parametric formula relating the frequencies of twin-peak quasi-periodic oscillations
• Broadband spectro-temporal investigation of neutron star low-mass X-ray binary GX 349+2
• X-ray polarization of Z-type neutron star low-mass X-ray binaries -- I. Model-independent, time-resolved X-ray polarimetry
• Classification of Power Density Spectrum Features and Estimation of the Delta-Invariant Value for the Z Source GX 340+0
• Timing Properties of Shocked Accretion Flows around Neutron Stars in Presence of Cooling
• Probing the accretion disc structure by the twin kHz QPOs and spins of neutron stars in LMXBs
• Morphological analysis on the coherence of kHz QPOs
• AstroSat View of Transient Low-mass X-ray Binary XTE J1701-462: Spectral and Temporal Evolution along the Z-track
• Study on Correlations between the Twin Kilohertz Quasi-periodic Oscillations in Low-mass X-ray Binaries
• Generalized Flows around Neutron Stars