Journal
ASTRONOMY & ASTROPHYSICS
Volume 472, Issue 2, Pages L25-L28Publisher
EDP SCIENCES S A
DOI: 10.1051/0004-6361:20078081
Keywords
gravitation; cosmology : dark matter; galaxies : dwarf; galaxies : kinematics and dynamics
Categories
Funding
- STFC [PP/D000890/1] Funding Source: UKRI
- Science and Technology Facilities Council [PP/D000890/1] Funding Source: researchfish
Ask authors/readers for more resources
Within the cold dark matter (CDM) framework tidal dwarf galaxies (TDGs) cannot contain dark matter, so the recent results by Bournaud et al. (2007, Science, 316, 1166) that 3 rotating TDGs do show significant evidence for being dark matter dominated is inconsistent with the current concordance cosmological theory unless yet another dark matter component is postulated. We confirm that the TDG rotation curves are consistent with Newtonian dynamics only if either an additional dark matter component is postulated, or if all 3 TDGs happen to be viewed nearly edge-on, which is unlikely given the geometry of the tidal debris. We also find that the observed rotation curves are very naturally explained without any free parameters within the modified Newtonian dynamics (MOND) framework if inclinations are adopted as derived by Bournaud et al. We explore different inclination angles and two different assumptions about the external field effect. The results do not change significantly, and we conclude therefore that Newtonian dynamics has severe problems while MOND does exceedingly well in explaining the observed rotation curves of the 3 TDGs studied by Bournaud et al.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available