Particle acceleration and radiation in pulsars
Pulsars shine throughout the electromagnetic spectrum, from radio waves to energetic gamma rays, but the origin of the emitted radiation is still poorly understood. The recent development of global particle-in-cell (PIC) simulations allows, for the first time, to address this problem from first principles and self-consistently. Three-dimensional radiative PIC simulations show that the equatorial current sheet forming in the pulsar wind is the main site of particle acceleration, instead of electrostatic gaps within the co-rotating magnetosphere as usually assumed. Relativistic reconnection dissipates magnetic energy which is then efficiently channeled into energetic particles and high-energy synchrotron radiation. Synthetic lightcurves, spectra and polarization present robust features reminiscent of observed gamma-ray pulsars. PIC simulations also suggest that general relativistic effects are essential to ignite pair creation at the star polar-cap, which may power the radio emission.