The correlations between the twin kHz QPO frequencies of LMXBs
نویسندگان
چکیده
We analyzed the recently published kHz QPO data in the neutron star low-mass X-ray binaries (LMXBs), in order to investigate the different correlations of the twin peak kilohertz quasi-periodic oscillations (kHz QPOs) in bright Z sources and in the less luminous Atoll sources. We find that a power-law relation ν1 ∼ ν 2 between the upper and the lower kHz QPOs with different indices: b ≃1.5 for the Atoll source 4U 1728-34 and b ≃1.9 for the Z source Sco X-1. The implications of our results for the theoretical models for kHz QPOs are discussed.
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