Unfolding of the vortical amplification of the magnetic field at inward shocks of Supernova remnant Cassiopeia A

Discussion timeslot (ZOOM-Meeting): 16. July 2021 - 12:00
ZOOM-Meeting URL: https://desy.zoom.us/j/92210078166
ZOOM-Meeting ID: 92210078166
ZOOM-Meeting Passcode: ICRC2021
Corresponding Session: https://icrc2021-venue.desy.de/channel/12-Galactic-Particle-Acceleration-including-PIC-CRI-CRD-MM/127
Live-Stream URL: https://icrc2021-venue.desy.de/livestream/Discussion-03/4

Abstract:
'Time variability of the X-ray flux of supernova remnants enables us to probe the evolution of the local magnetic field and the particle acceleration at interstellar shocks. High spatial resolution multiepoch (from 2000 to 2014) Chandra observations of Cassiopeia A supernova remnant have shown evidence of variation up to 50% of the 4.2-6 keV flux in six distinct regions located on the west side and toward the center of the remnant. We show that the [4.2-6] keV non-thermal flux increase traces the exponential growth of the magnetic field due to vortical amplification mechanism at reflection inward shocks colliding with inner outward clumps. The amplification occurs in the outer layer of the clumps where density gradient is non-vanishing (about 0.1 pc in this case). The fast synchrotron cooling as compared with shock-acceleration time scale qualitatively supports the flux decrease.'

Authors: Federico Fraschetti | Joe Giacalone | Satoru Katsuda | Toshiki Sato | J. Randy Jokipii
Indico-ID: 1306
Proceeding URL: https://pos.sissa.it/395/175