Diversity of dark matter density profiles in the Galactic dwarf spheroidal satellites

Understand

The core-cusp problem is one of the controversial issues in the standard paradigm of $\Lambda$ cold dark matter ($\Lambda$CDM) theory.

• However, under the assumption of conventional spherical symmetry, the strong degeneracy among model parameters makes it unclear whether dwarf spheroidal (dSph) galaxies indeed have cored dark matter density profiles at the centers.
• In this work, we revisit this problem using non-spherical mass models, which have the advantage of being able to alleviate the degeneracy.
• Applying our mass models to the currently available kinematic data of the eight classical dSphs, we find that within finite uncertainties, most of these dSphs favor cusped central profiles rather than cored ones.