The Gaseous Halo Mask
Support for spiral galaxies harboring an extended cosmologically significant gaseous halo is presented through evidence of the stripping of gas from dwarf galaxies in both observations and local and cosmological simulations. Dwarf galaxies within 270 kpc of the Milky Way and Andromeda are largely devoid of gas, and those with significant amounts of gas are beyond this radius. This is most easily explained by ram pressure stripping as the dwarfs move through perigalacticon. The star formation histories of the dwarf galaxies can also be partially understood in the context of their movement through this halo medium. Since the dwarfs are stripped at distances generally greater than 20 kpc, the gas is unlikely to make it directly into the spiral galaxy disk as cold star formation fuel. Some of the dwarfs’ gas may be integrated into the spiral galaxy’s hot halo and warm clumps may undergo a recooling process close to the disk.
KeywordsStar Formation Spiral Galaxy Dwarf Galaxy Star Formation Rate Dark Matter Halo
Unable to display preview. Download preview PDF.
Ken Freeman of course! Ken is a thesis advisor extraordinaire and an important role model. M.E.P. acknowledges funding from NSF grants AST-0904059, AST-0917810, the Luce Foundation, and the Research Corporation, and thanks David Block for his hard work organizing the conference. Computations were performed at the NASA Advanced Supercomputing (NAS) Division and at the National Center for Supercomputing Applications supported by the NSF.
- 1.Begum, A. et al. 2010, ApJ, in pressGoogle Scholar
- 9.Heitsch, F. et al. 2004, ApJ, 674, 316Google Scholar
- 10.Hsu, W., Putman, M.E., Heitsch, F., Stanimirovic, S., Peek, J.E.G., Clark, S.E., 2010, AJ, in pressGoogle Scholar
- 20.Slyz, A., Prendergast 1999, A&AS, 139, 199Google Scholar