Correlation of Diffusion Upstream of Shocks with Their Magnetic Compression: An Application of IMAP’s Living Catalog of Interplanetary Shocks
Year: 2026
Type: article
Abstract: We apply an automated routine to detect and catalog interplanetary shocks observed by the Interstellar Mapping and Acceleration Probe (IMAP). Using this catalog, we derive the upstream diffusion coefficient corresponding to 1 MeV protons along each shock’s normal direction using second-order quasi-linear theory and unified nonlinear transport theory to get the parallel and perpendicular components of the diffusion coefficient tensor, respectively. We show that the magnetic compression, as a proxy for shock strength, of fast forward shocks is statistically correlated with the upstream diffusion coefficient (Pearson correlation of 0.81 ± 0.13 and p -value of 0.014), suggesting that magnetic compression is related to the processes governing particle acceleration and particle transport near interplanetary shocks. This result is consistent with several possible interpretations, including changes in upstream turbulence, particle reflection, acceleration processes whose efficiency depends on shock compression and geometry, or a combination of these effects. We host the interplanetary shock catalog on the IMAP mission’s publicly available webpage and plan to regularly update it for use by the heliophysics community.
Authors: M. E. Cuesta, T. S. Horbury, J. S. Rankin, N. Subashchandar, L. Zhao, D. Turner, S. Raptis, H. A. Farooki, B. L. Shrestha, D. J. McComas, N. A. Schwadron, E. R. Christian, M. Gkioulidou, C. M. S. Cohen, S. Kasapis, L. Y. Khoo, N. K. Walia, R. N. Jain, S. Pak, M. M. Shen, E. J. Zirnstein, J. R. Szalay, G. Livadiotis, N. V. Sarlis, J. G. Mitchell, Z. Xu, G. D. Muro, J. Giacalone, W. H. Matthaeus, G. P. Zank
Institutions: Princeton University, University of Alabama in Huntsville, Johns Hopkins University Applied Physics Laboratory, Los Alamos National Laboratory, University of New Hampshire, Goddard Space Flight Center, California Institute of Technology, National and Kapodistrian University of Athens, University of Delaware
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
OpenAlex ID: W7221768230