On the HBO mechanism of X-ray neutron star

We ascribe the 15-60 Hz Quasi Periodic Oscillation (QPO) to the periastron precession frequency of the orbiting accreted matter at the boundary of mag netosphere-disk of Xray neutron star (NS). Considering the relativistic mot ion mechanism for the kHz QPO, that the radii of the inner disk and magneto sphere-disk of NS are correlated with each other by a factor is assumed. Th e obtained conclusions include: all QPO frequencies increase with increasin g the accretion rate. The theoretical relations between 15-60 Hz QPO (HBO) frequency and the twin kHz QPOs are similar to the measured empirical formu la. Further, the better fitted NS mass by the proposed model is about 1.9 s olar masses for the detected LMXBs.