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arXiv · 2602.23356

Revisiting the Perseus Cluster III: Role of Aspherical Explosions on its Chemical Composition and Extension to Metal-Poor Stars and Galaxies

Abstract

The Perseus Cluster has been precisely measured by the legacy Hitomi telescope on the Si-group (Si, S, Ar, Ca) and Fe-group elements (Cr, Mn, Ni). These element abundance ratios provide insight into the typical behaviour of supernovae. In Paper II, we presented new massive star explosion models at various metallicity, assuming spherical explosions. We show that while the fitting is improved, some features (e.g., Ni/Fe) remain to be improved. In this article, we extend our calculation to an aspherical explosion using the jet-induced explosion mechanism. The detailed pre- and post-explosion chemical profiles are calculated with a large post-processing network to capture the production of odd-number elements (V, Mn, Cu) and iron-group elements. We further explore how the jet-driven explosions create the diversity of models which could be compatible with the observed diversity in terms of $^{56}$Ni-mass vs ejecta mass, Ti-V relation, and stellar abundances. Finally, we apply the new collapsar models in the Galactic Chemical Evolution context. We study how the galactic stars, including the Zn-enriched star HE 1327-2326, can put constraints on the relative rates of collapsar and some of its model parameters. We show that collapsar could lead to significant changes in some elements, e.g., Zn. Our study shows that the collapsar is a necessary component to explain multiple elemental trends observed in the Milky Way Galaxy.

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Shing-Chi Leung, Henry Yerdon, Seth Walther, Ken'ichi Nomoto, Aurora Simionescu. 2026-02-26. Revisiting the Perseus Cluster III: Role of Aspherical Explosions on its Chemical Composition and Extension to Metal-Poor Stars and Galaxies. https://doi.org/10.3847/1538-4357/ae4d19

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