Low and high frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1

Details Low and high frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1 Low and high frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1

2002-02-22

arxiv.org/abs/astro-ph/0202420v1

Mon.Not.Roy.Astron.Soc. 333 (2002) 665

Astronomy and Astrophysics

Astrophysics

19 pages, 15 figures, Accepted for publication in MNRAS, 3 figures reduced in size, abstract abbreviated

Scientific paper

10.1046/j.1365-8711.2002.05442.x

We report on a detailed analysis of data obtained over nearly four years with the Rossi X-ray Timing Explorer of the Z source GX 5-1. From a spectral analysis using a hardness-intensity diagram it was found that the source traced out the typical Z-shaped pattern. The study of the power spectral properties showed that when the source moved on the Horizontal Branch towards the Normal Branch the fractional rms amplitudes and timescales of all variability decreased, while their FWHMs increased. The frequency separation of the two kHz QPO peaks decreased from 344+-12 Hz to 232+-13 Hz. At low frequencies, besides the horizontal branch oscillation (HBO) and its second harmonic, two additional broad Lorentzian components were needed to obtain acceptable fits. These broad Lorentzians have Q-values of ~1-2 and have frequencies 0.5 and 1.5 times the HBO frequency. When interpreted as being related to the HBO, they seem to favor disc models for the HBO over the magnetic beat-frequency model. We compare the timing properties and colour-colour diagrams (CDs) of GX 5-1 with those of the back hole candidate XTE J1550-564 and the atoll source 4U 1608-52. The CDs are strikingly similar when a colour scheme is used that is commonly employed in back hole studies. However, this may be a degeneracy as the CDs turn out to be more complicated when colours common in neutron star studies are employed. Apart from some remarkable similarities between the CD of XTE J1550-564 and that of 4U 1608-52, several differences can be seen between these CDs and that of GX 5-1. Conclusions on spectral states or properties based solely on the use of CDs using the ``black hole scheme'' should be regarded with caution.

Affiliated with

Also associated with

No associations

Rating

Low and high frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Low and high frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Low and high frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-339811