We point out an anticorrelation between the central dark matter (DM) densities of the bright Milky Way dwarf spheroidal galaxies (dSphs) and their orbital pericenter distances inferred from Gaia data. The dSphs that have not come close to the Milky Way centre (like Fornax, Carina and Sextans) are less dense in DM than those that have come closer (like Draco and Ursa Minor). The same anticorrelation cannot be inferred for the ultrafaint dSphs due to large scatter, while a trend that dSphs with more extended stellar distributions tend to have lower DM densities emerges with ultrafaints. We discuss how these inferences constrain proposed solutions to the Milky Way’s too-big-to-fail problem and provide new clues to decipher the nature of DM.
Kaplinghat, Manoj, et al. "Too big to fail in light of Gaia." Monthly Notices of the Royal Astronomical Society, vol. 490, no. 1, Sep. 2019. https://doi.org/10.1093/mnras/stz2511
Kaplinghat, Manoj, Valli, Mauro, & Yu, Hai-Bo (2019). Too big to fail in light of Gaia. Monthly Notices of the Royal Astronomical Society, 490(1). https://doi.org/10.1093/mnras/stz2511
Kaplinghat, Manoj, Valli, Mauro, and Yu, Hai-Bo, "Too big to fail in light of Gaia," Monthly Notices of the Royal Astronomical Society 490, no. 1 (2019), https://doi.org/10.1093/mnras/stz2511
@article{osti_1569296,
author = {Kaplinghat, Manoj and Valli, Mauro and Yu, Hai-Bo},
title = {Too big to fail in light of Gaia},
annote = {ABSTRACT We point out an anticorrelation between the central dark matter (DM) densities of the bright Milky Way dwarf spheroidal galaxies (dSphs) and their orbital pericenter distances inferred from Gaia data. The dSphs that have not come close to the Milky Way centre (like Fornax, Carina and Sextans) are less dense in DM than those that have come closer (like Draco and Ursa Minor). The same anticorrelation cannot be inferred for the ultrafaint dSphs due to large scatter, while a trend that dSphs with more extended stellar distributions tend to have lower DM densities emerges with ultrafaints. We discuss how these inferences constrain proposed solutions to the Milky Way’s too-big-to-fail problem and provide new clues to decipher the nature of DM.},
doi = {10.1093/mnras/stz2511},
url = {https://www.osti.gov/biblio/1569296},
journal = {Monthly Notices of the Royal Astronomical Society},
issn = {ISSN 0035-8711},
number = {1},
volume = {490},
place = {United Kingdom},
publisher = {Oxford University Press},
year = {2019},
month = {09}}
Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 1 Vol. 490; ISSN 0035-8711