Correlated Frequency-Changes of Trapped Vertical p-Mode Oscillations and kHz QPOs
نویسنده
چکیده
We have examined the frequencies of trapped two-armed (m = 2) nearly vertical oscillations (vertical p-mode) in vertically isothermal disks with toroidal magnetic fields. The magnetic fields are stratified so that the Alfvén speed, cA, is constant in the vertical direction. We have particularly focused our attention on how frequencies of the fundamental mode (nr = 0) and first overtone (nr = 1) in the radial direction change with the correlation, when the ratio c A=c 2 s changes, cs being the isothermal acoustic speed. The results show that in the case where the oscillations are the fundamental mode (n= 1) in the vertical direction, the correlated frequency changes of the above-mentioned oscillations seem to well describe, with standard values of the mass and spin of the central sources, the frequency correlation of kHz QPOs observed in neutron-star X-ray binaries.
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