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arXiv · 2510.04857

Joint eROSITA and H.E.S.S. analysis of MSH 15-52 using Gammapy

Abstract

Pulsar wind nebulae (PWNe) are prominent sources in the very-high energy (VHE) gamma-ray sky, constituting the most numerous identified source class in the H.E.S.S. Galactic Plane Survey (HGPS). They are comprised of energetic particles originating from the pulsar and expanding into the surrounding medium. As such, PWNe are of very high scientific interest as PeVatron candidates, objects that could potentially accelerate particles up to PeV energies. Additionally other aspects of their acceleration mechanism are being actively investigated, such as the open question of whether they accelerate not only leptonic but also hadronic particles, and the details of their morphology and particle transport mechanism. As PWNe emit photons over a broad range of the electromagnetic spectrum, multiwavelength (MWL) studies are crucial for the investigation and study of their emission. In this vein we present a joint eROSITA X-ray and H.E.S.S. gamma-ray study of the PWN MSH 15-52. We showcase our custom code for integrating the EDR and DR1 eROSITA data into the Gammapy framework, a python package optimised for the analysis of gamma-ray data. We present the first 3D (spatial and spectral) fit to eROSITA data by using Gammapy. We furthermore combine these data with the public H.E.S.S. gamma-ray observations of MSH 15-52, resulting in a joint physical fit of the underlying particle population, and a subsequent discussion of the physical implications of our results. Finally we give an outlook towards future efforts in MWL studies of PWNe and the broader context of MWL data analysis with Gammapy.

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BibTeXRIS

Katharina Egg, Alison M. W. Mitchell. 2025-10-06. Joint eROSITA and H.E.S.S. analysis of MSH 15-52 using Gammapy. https://doi.org/10.22323/1.501.0637

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