Inner Halo Shapes of Dwarf Galaxies: Reconciling the Cusp/Core Problem

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We derive inner dark matter halo density profiles for a sample of 200 dwarf galaxies by inverting rotation curves obtained from high-quality, long-slit optical spectra. Each galaxy in the sample shows no evidence for a bulge, bar or other baryonic distortions as determined by accurate I-band photometry. For ρ (r) ˜\ r-α near the galaxy center we obtain a distribution of measured inner profile slopes α m that peaks at α m ˜\ 0.3, similar to values found by other authors (e.g. de Blok et al. 2003, Swaters et al. 2003), and in stark contrast to the intrinsic cusps (α int ˜\ 1) predicted by simulations of halo assembly in CDM cosmologies. To assess the severity of the discrepancy between our results and CDM predictions, we simulate long-slit observations of a population of intrinsically cuspy (α int =1) dwarf halos. The large sample size in this study permits a quantitative comparison between theory and observations, in which the impact of a variety of observational and data processing biases can be analyzed in a statistically significant manner. Our simulations recover both the observed distribution of α m and correlations between α m and primary observational parameters such as distance and disk inclination. We conclude that, in our long-slit spectroscopy data sample, the observations are consistent with cuspy halos as predicted by the CDM paradigm without recourse to halo triaxiality, modifications of Newtonian dynamics or other exotic phenomena. This work is partially funded by NSF grants AST-9900695 and AST-0307661.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Inner Halo Shapes of Dwarf Galaxies: Reconciling the Cusp/Core Problem 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 Inner Halo Shapes of Dwarf Galaxies: Reconciling the Cusp/Core Problem, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Inner Halo Shapes of Dwarf Galaxies: Reconciling the Cusp/Core Problem will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1422254

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.