The high energy emission of the Crab’s twin pulsar PSR J0540-6919 in the Large Magellanic Cloud

In the present paper, we discuss theoretical interpretation of the X-ray and gamma-ray emission of the extremely bright pulsar PSR J0540-6919, in the Large Magellanic cloud. The source of the high frequency emission is assumed to be the synchrotron radiation, which is generated near the light cylinder during the quasi-linear stage of the cyclotron instability developed in this region. The emitting particles are the particles of the primary beam, with the Lorentz factors of the order of γ b ∼ 10 7 that provide generation of the gamma-ray emission with the photon energy up to 10 GeV and the secondary plasma electrons with γ t ∼ 10 5 , emitting in the X-ray domain. The theoretical synchrotron radiation spectra obtained in the framework of the model provide natural explanation of the observed photon spectra showing power-law indices 2.2 for gamma-rays and 1.55 for the X-rays. The present model provides natural explanation for pulse-aligned emission peaks at different frequencies and smearing of two-peak pulse profile at higher frequencies that is clearly observed in radio domain.