We briefly review the proposed relations between the frequencies of twin kilohertz quasi-periodic oscillations(kHz QPOs) and the spin frequencies in neutron star low-mass X-ray binaries(NSLMXBs).To test the validity o...We briefly review the proposed relations between the frequencies of twin kilohertz quasi-periodic oscillations(kHz QPOs) and the spin frequencies in neutron star low-mass X-ray binaries(NSLMXBs).To test the validity of the proposed models,we estimate the spin frequencies under these theoretical relations and compare them with the measured ones.It seems that magnetohydrodynamic(MHD) oscillations are more promising to account for the kHz QPOs.展开更多
Based the Alfven wave oscillation model(AWOM) and relativistic precession model(RPM) for twin kHz QPOs,we estimate the emission positions of most detected kHz QPOs to be at r=18+/-3 km(R/15 km),except Cir X-1 at r-30+...Based the Alfven wave oscillation model(AWOM) and relativistic precession model(RPM) for twin kHz QPOs,we estimate the emission positions of most detected kHz QPOs to be at r=18+/-3 km(R/15 km),except Cir X-1 at r-30+/-5 km(R/15 km).For the proposed Keplerian frequency as an upper limit to kHz QPO,the spin effects in Kerr Spacetime are discussed,which have about a 5%(2%) modification for that of the Schwarzchild case for the spin frequency of 1000(400) Hz.The application to the four typical QPO sources,Cir X-1,Sco X-1,SAX J1808.4-3658 and XTE 1807-294,is mentioned.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 10873008)the National Basic Research Program of China (Grant No. 2009CB824800)
文摘We briefly review the proposed relations between the frequencies of twin kilohertz quasi-periodic oscillations(kHz QPOs) and the spin frequencies in neutron star low-mass X-ray binaries(NSLMXBs).To test the validity of the proposed models,we estimate the spin frequencies under these theoretical relations and compare them with the measured ones.It seems that magnetohydrodynamic(MHD) oscillations are more promising to account for the kHz QPOs.
基金supported by the National Basic Research Program of China (Grant No. 2009CB824800)the National Natural Science Foundation of China (Grant No. 10773017)
文摘Based the Alfven wave oscillation model(AWOM) and relativistic precession model(RPM) for twin kHz QPOs,we estimate the emission positions of most detected kHz QPOs to be at r=18+/-3 km(R/15 km),except Cir X-1 at r-30+/-5 km(R/15 km).For the proposed Keplerian frequency as an upper limit to kHz QPO,the spin effects in Kerr Spacetime are discussed,which have about a 5%(2%) modification for that of the Schwarzchild case for the spin frequency of 1000(400) Hz.The application to the four typical QPO sources,Cir X-1,Sco X-1,SAX J1808.4-3658 and XTE 1807-294,is mentioned.
