Resonant cyclotron scattering （RCS） in pulsar magnetospheres is considered. The photon diffusion equation （Kompaneets equation） for RCS is derived. The photon system is modeled three dimensionally. Numerical calcu...Resonant cyclotron scattering （RCS） in pulsar magnetospheres is considered. The photon diffusion equation （Kompaneets equation） for RCS is derived. The photon system is modeled three dimensionally. Numerical calculations show that there exist not only up scattering but also down scattering of RCS, depending on the parameter space. RCS＇s possible applications to spectral energy distributions of magnetar candidates and radio quiet isolated neutron stars （INSs） are pointed out. The optical/UV excess of INSs may be caused by the 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 proposed to be normal neutron stars, although the quark star hypothesis is still possible. The low pulsation amplitude of INSs is a natural consequence in the RCS model.展开更多
X-ray dim isolated neutron stars are peculiar pulsar-like objects, characterized by their Planck-like spectrum. In studying their spectral energy distributions, optical/ultraviolet （UV） excess is a long standing pro...X-ray dim isolated neutron stars are peculiar pulsar-like objects, characterized by their Planck-like spectrum. In studying their spectral energy distributions, optical/ultraviolet （UV） excess is a long standing problem. Recently Kaplan et al. measured the optical/UV excess for all seven sources, which is understandable in the resonant cyclotron scattering （RCS） model previously addressed. The RCS model calculations show that the RCS process can account for the observed optical/UV excess for most sources. The flat spectrum of RX J2143.0＋0654 may be due to contributions from the bremsstrahlung emission of the electron system in addition to the RCS process.展开更多
基金Supported by the National Natural Science Foundation of China
文摘Resonant cyclotron scattering （RCS） in pulsar magnetospheres is considered. The photon diffusion equation （Kompaneets equation） for RCS is derived. The photon system is modeled three dimensionally. Numerical calculations show that there exist not only up scattering but also down scattering of RCS, depending on the parameter space. RCS＇s possible applications to spectral energy distributions of magnetar candidates and radio quiet isolated neutron stars （INSs） are pointed out. The optical/UV excess of INSs may be caused by the 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 proposed to be normal neutron stars, although the quark star hypothesis is still possible. The low pulsation amplitude of INSs is a natural consequence in the RCS model.
基金supported by the National Natural Science Foundation of China (NSFC, GrantNos. 10935001 and 10973002)the National Basic Research Program of China (973 Program, Grant No. 2009CB824800)the John Templeton Foundation
文摘X-ray dim isolated neutron stars are peculiar pulsar-like objects, characterized by their Planck-like spectrum. In studying their spectral energy distributions, optical/ultraviolet （UV） excess is a long standing problem. Recently Kaplan et al. measured the optical/UV excess for all seven sources, which is understandable in the resonant cyclotron scattering （RCS） model previously addressed. The RCS model calculations show that the RCS process can account for the observed optical/UV excess for most sources. The flat spectrum of RX J2143.0＋0654 may be due to contributions from the bremsstrahlung emission of the electron system in addition to the RCS process.
