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arXiv · 2512.03890

The May 2024 Storm: dayside magnetopause and cusps in simulated soft X-Rays

Abstract

The coronal mass ejection (CME) arriving at Earth on May 10, 2024 caused the most intense geomagnetic storm in the last two decades, and resulted in highly unusual magnetopause and cusp dynamics. We simulate soft X-Ray emission due to solar wind charge exchange with exospheric neutrals to image the global dayside dynamics, focusing on the impact of a dense CME current sheet during the storm main phase. The magnetopause moves inward to ~ 4 RE, and at the same time, the two cusps manifest as nearly parallel emission ridges in X-Ray. As the interplanetary magnetic field reverses, the cusp ridges move to higher latitudes for ~ 10 minutes after the reversal. The X-Ray emission can be detected by imagers to be flown on future missions to provide a global picture of the magnetopause and cusps with quantitative determination of their locations

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J. Ng, L. -J. Chen, B. Burkholder, D. Sibeck, F. S. Porter, K. H. Pham, V. G. Merkin, H. Connor, J. W. Bonnell, S. Petrinec, Y. Zou, B. Alterman, G. Cucho-Padin. 2025-12-03. The May 2024 Storm: dayside magnetopause and cusps in simulated soft X-Rays. https://arxiv.org/abs/2512.03890

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