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arXiv · 2506.19721

MUSE-DARK-I: Dark matter halo properties of intermediate-z star-forming galaxies

B. I. Ciocan·N. F. Bouché·J. Fensch·W. Mercier·D. Krajnović·J. Richard·T. Contini·A. Jeanneau
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Abstract

[Abridged] We analyse the dark matter (DM) halo properties of 127 0.3 80% of the sample. We find that the kinematically inferred stellar masses agree with values from SED fitting. We find that 89% of galaxies have DM fractions >50%. For 66% of SFGs, we infer a DM inner slope, gamma < 0.5, indicating cored DM profiles, but no correlation is found between gamma and star formation rate of the sample. The stellar- and concentration-mass relations agree with theoretical expectations, but with larger scatter. We confirm the anticorrelation between halo scale radius and DM density. The halo scale radii and DM surface densities increase with Mstar, while DM densities stay constant. We find tentative evidence of an evolution of the DM density with z, which suggests that the DM halos of intermediate-z systems are denser than those of local galaxies. In contrast, the halo scale radii are z-invariant.

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B. I. Ciocan, N. F. Bouché, J. Fensch, W. Mercier, D. Krajnović, J. Richard, T. Contini, A. Jeanneau. 2025-06-24. MUSE-DARK-I: Dark matter halo properties of intermediate-z star-forming galaxies. https://doi.org/10.1051/0004-6361%2F202557396

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