Revealing mass distributions of dwarf spheroidal galaxies in the Subaru-PFS era

Kohei Hayashi; Laszlo Dobos; Carrie Filion; Evan Kirby; Masashi Chiba; Rosemary F. G. Wyse; PFS Galactic Archaeology Science Working Group

arXiv · 2305.11309

Revealing mass distributions of dwarf spheroidal galaxies in the Subaru-PFS era

Kohei Hayashi·Laszlo Dobos·Carrie Filion·Evan Kirby·Masashi Chiba·Rosemary F. G. Wyse·PFS Galactic Archaeology Science Working Group

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Abstract

The Galactic dwarf spheroidal galaxies (dSphs) provide valuable insight into dark matter (DM) properties and its role in galaxy formation. Their close proximity enables the measurement of line-of-sight velocities for resolved stars, which allows us to study DM halo structure. However, uncertainties in DM mass profile determination persist due to the degeneracy between DM mass density and velocity dispersion tensor anisotropy. Overcoming this requires large kinematic samples and identification of foreground contamination. With 1.25 deg$^2$ and 2394 fibers, PFS plus pre-imaging with Hyper Suprime Cam will make significant progress in this undertaking.

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Kohei Hayashi, Laszlo Dobos, Carrie Filion, Evan Kirby, Masashi Chiba, Rosemary F. G. Wyse, PFS Galactic Archaeology Science Working Group. 2023-05-18. Revealing mass distributions of dwarf spheroidal galaxies in the Subaru-PFS era. https://arxiv.org/abs/2305.11309

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