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arXiv · 2609.01715

Measuring Small-scale Turbulence in Supernova Remnants with Jitter Radiation

Emily Simon·Damiano Caprioli·Niccolò Bucciantini·Emanuele Greco·Marco Miceli
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Abstract

Hard X-ray emission from Cas A has been attributed to jitter radiation, implying magnetic turbulence on scales near or below the ion Larmor radius. We propose these fields arise from ion-scale micro-instabilities (e.g., mirror and firehose) in the shock downstream, and use high-resolution hybrid simulations to demonstrate the generation of such small-scale turbulence. Its spectral index, once numerical dissipation is accounted for, is consistent with that inferred for Cas A, suggesting that jitter radiation is a direct probe of ion-scale turbulence in supernova remnants.

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Emily Simon, Damiano Caprioli, Niccolò Bucciantini, Emanuele Greco, Marco Miceli. 2026-09-01. Measuring Small-scale Turbulence in Supernova Remnants with Jitter Radiation. https://arxiv.org/abs/2609.01715

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