Timing and spectral study of XB 1254-690 using new RXTE PCA data

Details Timing and spectral study of XB 1254-690 using new RXTE PCA data Timing and spectral study of XB 1254-690 using new RXTE PCA data

2011-07-20

arxiv.org/abs/1107.3993v1

Monthly Notices of the Royal Astronomical Society, 03/2011, Volume 411, Issue 4, pp. 2717-2725

Astronomy and Astrophysics

Astrophysics

High Energy Astrophysical Phenomena

16 pages, 6 figures, 4 tables; published in MNRAS

Scientific paper

10.1111/j.1365-2966.2010.17872.x

We have analyzed the new Rossi X-ray Timing Explorer Proportional Counter Array data of the atoll neutron star (NS) low-mass X-ray binary (LMXB) system XB 1254-690. The colour-colour diagram shows that the source was in the high-intensity banana state. We have found two low-frequency candidate peaks with single trial significances of ~ 2.65 X 10^{-8} and ~ 7.39 X 10^{-8} in the power spectra. After taking into account the number of trials, the joint probability of appearance of these two peaks in the data set only by chance is ~ 4.5 X 10^{-4}, and hence a low-frequency QPO can be considered to be detected with a significance of ~ 4.5 X 10^{-4}, or, ~ 3.5\sigma for the first time from this source. We have also done the first systematic X-ray spectral study of XB 1254-690, and found that, while one-component models are inadequate, three-component models are not required by the data. We have concluded that a combined broken-powerlaw and Comptonization model best describes the source continuum spectrum among 19 two-component models. The plasma temperature (~ 3 keV) and the optical depth (~ 7) of the Comptonization component are consistent with the previously reported values for other sources. However, the use of a broken-powerlaw component to describe NS LMXB spectra has recently been started, and we have used this component for XB 1254-690 for the first time. We have attempted to determine the relative energy budgets of the accretion disc and the boundary layer using the best-fit spectral model, and concluded that a reliable estimation of these budgets requires correlations among time variations of spectral properties in different wavelengths.

Affiliated with

Also associated with

No associations

Rating

Timing and spectral study of XB 1254-690 using new RXTE PCA data 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 Timing and spectral study of XB 1254-690 using new RXTE PCA data, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Timing and spectral study of XB 1254-690 using new RXTE PCA data will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-35694