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arXiv · 2510.09559

Direct observation of the X-ray counterpart of the H{\alpha} filaments and of the sloshing spiral in the Perseus galaxy cluster

Adrien Picquenot·Fabio Acero·Valeria Olivares·Michela Negro·Gabriel W. Pratt
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Abstract

Deep Chandra observations of the Perseus galaxy cluster have allowed for the discovery of X-ray counterparts to the H{\alpha} filamentary structures and of a sloshing spiral. However, both components are extremely faint, and their study is largely hindered by the volume-filling hot intracluster medium (ICM). Using the Poisson General Morphological Component Analysis (pGMCA) algorithm, a blind source separation method adapted for Poissonian statistics, we were able to extract detailed, clean morphological maps of these components. We then introduced a template fitting method to investigate their spectral characteristics. We report the first direct observation of about 1.35 keV low-energy emission from the sloshing spiral, and produce the most detailed and unpolluted map of the X-rays filaments thus far obtained.

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Adrien Picquenot, Fabio Acero, Valeria Olivares, Michela Negro, Gabriel W. Pratt. 2025-10-10. Direct observation of the X-ray counterpart of the H{\alpha} filaments and of the sloshing spiral in the Perseus galaxy cluster. https://doi.org/10.3847/2041-8213%2Fae14fc

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