Letter to the Editor A model for the binary pulsar radio eclipse

A problem of the binary pulsar radio eclipses is considered. Recent theoretical work concerning this problem is discussed and a plasma mechanism of radio eclipses in the PSR B1957+20 binary system is presented. The companion star is assumed tobe adegeneratewhite dwarfwith nearly dipolarmagnetosphere filled with relativistic particles of the pulsar wind. It is argued that radio waves are strongly damped in the companion’s magnetosphere due to the cyclotron resonance with particles of the electron-positron plasma. The large, stable, continuous and frequency-dependent eclipses should occur as a result of this process, which agrees well with observations. Possible mechanisms of generation of the optical and high-energy emission are also suggested in the framework of the presentedmodel.