On Pulsed Multi-Band Emission from TeV Gamma Rays to Radio Waves in the Crab and Velar Pulsar
Bi-Ping Gong
On Pulsed Multi-Band Emission from TeV Gamma Rays to Radio Waves in the Crab and Velar Pulsar
On Pulsed Multi-Band Emission from TeV Gamma Rays to Radio Waves in the Crab and Velar Pulsar
摘要
Increasing observations of pulsed TeV γ-rays, i.e., in Vela[1] and Crab pulsar[2] [3] set unprece- dented constraints on mechanism and location of pulsar emission. In particular, how such ultra-high energy radiation (UHE) usually treated as incoherent be nearly in phased with coherent radio emis- sion, and thus achieving an approximately in phased multiband emission have not been understood. Here shows that fast spin velocity and strong strength of surface magnetic field of a pulsar result in accumulation of magnetic energy near the light cylinder. As a bundle of last closed field lines at such a energy reservoir is carried across the light cylinder by magnetocentrifugal, a forced reconnec- tion is triggered at the tip of the last closed field lines generating pair production. The resultant particle-wave resonance at the tiny reconnection site is analogous to the Free Electron Laser (FEL) process[4–6] where high-energy electrons are deflected, focused, and guided by magnetic fields, invok- ing coherent synchrotron emission responsible for pulsed TeV emission. Propagating of such a TeV γ-ray emission along the flux tube surrounding the tiny reconnection region leads to pair cascade responsible for multiband emission from 102MeV to radio. As each reconnection event corresponds to a microstructure with cone-core pattern, radiation of microstructure in multiband should exhibit similar morphology and polarization behavior. And a fluctuation in strength of magnetic field at the reconnection site can give rise to pulsed PeV γ-ray emission.
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