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Kilohertz quasi-periodic oscillations and strong field gravity in X-ray binaries

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 نشر من قبل Mariano Mendez
 تاريخ النشر 2002
  مجال البحث فيزياء
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 تأليف Mariano Mendez




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In the past five years observations with the Rossi X-ray Timing Explorer have revealed fast quasi-periodic oscillations in the X-ray flux of about 20 X-ray binaries. Thought to originate close to the surface of a neutron star, these oscillations provide unique information about the strong gravitational field in which they are produced.



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The recently updated data of the twin kilohertz quasi-periodic oscillations (kHz QPOs) in the neutron star low-mass X-ray binaries are analyzed. The power-law fitting $ u_{1}=a( u_{2}/1000)^{b}$ and linear fitting $ u_{2}=A u_{1}+B$ are applied, indi vidually, to the data points of four Z sources (GX 17+2, GX 340+0, GX 5-1 and Sco X-1) and four Atoll sources (4U 0614+09, 4U 1608-52, 4U 1636-53 and 4U 1728-34). The $chi^{2}$-tests show that the power-law correlation and linear correlation both can fit data well. Moreover, the comparisons between the data and the theoretical models for kHz QPOs are discussed.
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