Publication date: Dec 2007
Abstract:
Relation between the lower and upper frequency mode of twin peak
quasiperiodic oscilations observed in neutron star X-ray binaries is
qualitatively well fitted by the frequency relation following from the
relativistic precession model. Assuming this model with no preferred
radius and the probability of a twin QPO excitation being uniform across
the inner edge of an accretion disc, we compare the expected and
observed twin peak QPO distribution in the case of atoll source 4U
1636-53. We find these two distributions highly incompatible. We also
find that the observed distribution roughly corresponds to the expected
one if an additional consideration of preferred resonant orbits is
included. We notice that our findings are relevant for some
disc-oscillation QPO models as well.
Authors:
Török, Gabriel; Bakala, Pavel; Stuchlík, Zdeněk; Čech, Petr;