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arXiv · 2109.07545

The MUSE Extremely Deep Field: Evidence for SFR-induced cores in dark-matter dominated galaxies at z=1

Nicolas F. Bouché·Samuel Bera·Davor Krajnovic·Eric Emsellem·Wilfried Mercier·Joop Schaye·Benoît Épinat·Johan Richard·Sebastiaan L. Zoutendijk·Valentina Abril-Melgarejo·Jarle Brinchmann·Roland Bacon·Thierry Contini·Leindert Boogaard·Lutz Wisotzki·Michael Maseda·Matthias Steinmetz
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Abstract

Disc-halo decomposition on rotationally supported star-forming galaxies (SFGs) at $z>1$ are often limited to massive galaxies ($M_\star>10^{10}~M_\odot$) and rely on either deep Integral Field Spectroscopy data or stacking analyses. We present a study of the dark matter (DM) content of nine $z\approx1$ SFGs selected Using the brightest [OII] emitters in the deepest Multi-Unit Spectrograph Explorer (MUSE) field to date, namely the 140hr MUSE Extremely Deep Field, we perform disk-halo decompositions on 9 low-mass SFGs (with $10^{8.5} 10^{10}~M_\odot$. The DM halos show constant surface densities of $\sim100~M_\odot$ pc$^{-2}$. Half of the sample shows a strong preference for cored over cuspy DM profiles. The presence of DM cores appears to be related to galaxies with stellar-to-halo mass $\log M_\star/M_{\rm vir}\approx-2.5$. In addition, the cuspiness of the DM profiles is found to be a strong function of the recent star-formation activity. Both of these results are interpreted as evidence for feedback-induced core formation in the Cold Dark Matter context.

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Nicolas F. Bouché, Samuel Bera, Davor Krajnovic, Eric Emsellem, Wilfried Mercier, Joop Schaye, Benoît Épinat, Johan Richard, Sebastiaan L. Zoutendijk, Valentina Abril-Melgarejo, Jarle Brinchmann, Roland Bacon, Thierry Contini, Leindert Boogaard, Lutz Wisotzki, Michael Maseda, Matthias Steinmetz. 2021-09-15. The MUSE Extremely Deep Field: Evidence for SFR-induced cores in dark-matter dominated galaxies at z=1. https://doi.org/10.1051/0004-6361%2F202141762

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