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arXiv · 2609.34421

Discovery of Kolmogorov-like turbulence in the inner shell of SNR HB 9

Li Xiao·Ming Zhu·Xiao-Hui Sun·Wolfgang Reich·Patricia Reich
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Abstract

We investigated the scaling relation of the magnetohydrodynamic turbulence in the inner and outer shells of the supernova remnant HB 9 using multi-tracers. For the eastern inner shell section, one-dimensional structure function and power spectrum analyses of the radio total intensity, H-alpha emission, and polarized intensity consistently show a Kolmogorov-like scaling of l^2/3 over the inertial range. The two-dimensional power spectrum for the entire inner region follows k^-8/3 of all tracers, including the polarization gradient. It indicates that fully developed, trans-Alfvenic Kolmogorov turbulence is present in the inner shell of HB 9. We estimated the strength of random magnetic field therein from the low fractional polarization (5%), and obtained a upper limit delta B of 18 micro G. The turbulence in the inner shock shell is most likely driven by the Richtmyer-Meshkov instability.

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Li Xiao, Ming Zhu, Xiao-Hui Sun, Wolfgang Reich, Patricia Reich. 2026-09-28. Discovery of Kolmogorov-like turbulence in the inner shell of SNR HB 9. https://arxiv.org/abs/2609.34421

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