Physics
Scientific paper
Aug 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008noao.prop..397m&link_type=abstract
NOAO Proposal ID #2008B-0397
Physics
Scientific paper
The nearby dwarf spheroidal (dSph) galaxies are particularly interesting as they arguably correspond to the smallest dark matter halos ever formed. As such they provide a possible direct link to the structures of the early Universe from which larger galaxies were assembled. Our large-scale kinematic study of nearby dSph galaxies reveals that even remote satellite systems exhibit some evidence of tidal effects with the Milky Way. Mass models using simple (and tractable) equilibrium dynamical models certainly become incorrect at a radius where the tides can be shown to be important. We propose to explore the importance of tidal perturbations in the kinematics of nearby dwarfs by using dwarf Cepheids to measure the line-of-sight depth of the Southern dSph galaxy, Fornax, that shows signs of spatial and kinematic substructure. (From data of December 2007, currently under analysis, we have found more than 100 dwarf Cepheids in Carina, a galaxy that shows some evidence for tidal streaming.) These data in the third spatial dimension strongly constrain specific orbital models of tidal perturbations and give us quantitative estimates of the magnitude of tidal heating. We can then produce more realistic dynamical models that, in turn, provide better estimates of the masses and extents of the underlying dark halos of these galaxies. Our approach can detect depths as small as (Delta) DoverD 5%, which can easily distinguish between models where tides or substructure dominate, from those where such effects only mildly perturb equilibrium dynamics.
Mateo Mario
Olszewski Edward
Walker Matthew
No associations
LandOfFree
Exploring the 3rd Dimension: The Line-of-Sight Depth of the Fornax dSph Galaxy does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Exploring the 3rd Dimension: The Line-of-Sight Depth of the Fornax dSph Galaxy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Exploring the 3rd Dimension: The Line-of-Sight Depth of the Fornax dSph Galaxy will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1806621