Correlations between X-ray spectra and kHz QPOS in Sco X-1

被引：0

作者：

Bradshaw, Charles F. ^{[1
,2
]}

Titarchuk, Lev ^{[2
,3
,4
]}

Kuznetsov, Sergey ^{[5
,6
]}

机构：

[1] MITRE Corp, McLean, VA 22102 USA

[2] George Mason Univ, Ctr Earth Observing & Space Res, Fairfax, VA 22030 USA

[3] US Naval, Res Lab, Washington, DC 20375 USA

[4] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA

[5] Univ Calif Riverside, ISPP, Riverside, CA 92521 USA

[6] Russian Acad Sci, Space Res Inst, Moscow R-117997, Russia

来源：

POPULATION EXPLOSION: THE NATURE AND EVOLUTION OF X-RAY BINARIES IN DIVERSE ENVIRONMENTS | 2008年 / 1010卷

关键词：

D O I：

暂无

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Recent analysis of the RXTE X-ray spectra of Sco X-1 discovered that Sco X-1 can be adequately modeled by a simple two-component model of Compton up-scattering with a soft photon electron temperature of about 0.4 keV, plus an Iron K-line. The results show a strong correlation between spectral power law index and kHz laPOs. Sco X-1 is the prototypical Z-source low-mass X-ray binary (LMXB) system radiating near the Eddington limit. This radiation produces a high radiation pressure in its Compton cloud. We infer that the radiation pressure produces a geometrical configuration of the cloud that is quasi-spherical. We conclude that the high Thomson optical depth of the Compton cloud, in the range of 5-6 from the best-fit model parameters, is consistent with the neutron star's surface being obscured by material, which would likely suppress a spin frequency of Sco X-1 due to photon scattering off cloud electrons. We also demonstrate the evolution of its power spectrum when Sco X-1 transitions from the horizontal branch to the normal branch.

引用

页码：180 / +

页数：2