Kompaneets equation for resonant cyclotron scattering and its application to isolated neutron stars
نویسندگان
چکیده
Resonant cyclotron scattering (RCS) in pulsar magnetospheres is considered. The photon diffusion equation (Kompaneets equation) for RCS is derived. After some deductions, a generalized form of Kompaneets equation is obtained. The numerical calculations show that there exist not only up scattering but also down scattering of RCS, depending on the parameter space. Its possible applications to magnetar soft X-ray emission and isolated neutron stars (INSs) are point out. The optical/UV excess of the INSs may be due to down scattering of RCS. The calculations for RX J1856.5-3754 and RX J0720.4-3125 are presented and compared with their observational data. In our model, the INSs are generally proposed to be normal neutron stars, although the quark star hypothesis is still possible. The low pulsation amplitude of the INSs is a natural consequence in the RCS model.
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