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arXiv · 1805.05951

Vortical amplification of magnetic field at inward shock of supernova remnant Cassiopeia A

F. Fraschetti·S. Katsuda·T. Sato·J. R. Jokipii·J. Giacalone
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Abstract

We present an interpretation of the time variability of the $X$-ray flux recently reported from a multi-epoch campaign of $15$ years observations of the supernova remnant Cassiopeia A by {\it Chandra}. We show for the first time quantitatively that the $[4.2-6]$ keV non-thermal flux increase up to $50\%$ traces the growth of the magnetic field due to vortical amplification mechanism at a reflection inward shock colliding with inner overdensities. The fast synchrotron cooling as compared with shock-acceleration time scale qualitatively supports the flux decrease.

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F. Fraschetti, S. Katsuda, T. Sato, J. R. Jokipii, J. Giacalone. 2018-05-15. Vortical amplification of magnetic field at inward shock of supernova remnant Cassiopeia A. https://doi.org/10.1103/physrevlett.120.251101

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