A wind model for high energy pulses

A solution to the σ problem — that of finding a mechanism capable of converting Poynting energy flux to particle-borne energy flux in a pulsar wind — was proposed several years ago by Coroniti and Michel who considered a particular prescription for magnetic reconnection in a striped wind. This prescription was later shown to be ineffective. In this paper, we discuss the basic microphysics of the reconnection process and conclude that a more rapid prescription is permissible. Assuming dissipation to set in at some distance outside the light-cylinder, we compute the resulting radiation signature and find that the synchrotron emission of heated particles appears periodic, in general showing both a pulse and an interpulse. The predicted spacing of these agrees well with observation in the case of the Crab and Vela pulsars. Using parameters appropriate for the Crab pulsar — magnetization parameter at the light cylinder σL = 6× 10 , Lorentz factor Γ = 250 — reasonable agreement is found with the observed total pulsed luminosity. This suggest that the high-energy pulses from young pulsars originate not in the co-rotating magnetosphere within the light cylinder (as in all other models) but from the radially directed wind well outside it.