Cosmic ray acceleration and high energy neutrinos at supernova explosions

by Gwenael Giacinti (University of Oxford)

Monday 13 Jan 2014, 14:30 → 15:30 Europe/Berlin

Building 67, SemRm 10 (DESY Hamburg)

Galactic cosmic rays (CR) are thought to be accelerated in supernova (SN) remnants, via diffusive shock acceleration (DSA). Studying the onset of CR acceleration during the first few days/years after the SN explosion is important, because of the high energies that might be reached then. DSA requires the presence of a collisionless shock (CS), but the shock is initially mediated by radiation and cannot accelerate suprathermal protons to relativistic energies. We study the transition from such shocks to CS. The CS is usually assumed to form soon after SN shock breakout. We demonstrate here, for the first time, that this does not hold for some progenitors enshrouded in optically thick winds. CR acceleration can start significantly earlier. We show that their secondary high energy neutrinos (at least E > 100 GeV - TeV) can reach the observer several hours before the first photons from breakout, enabling one to study the otherwise inaccessible optically thick regions of circumstellar winds.

Slides Giacinti_Hamburg_Jan13.pdf