PI: Heather Morrison, CWRU, firstname.lastname@example.org
Address: 10900 Euclid Ave, Cleveland, OH 44106
CoI: Denise Hurley-Keller, CWRU
CoI: Paul Harding, Steward Observatory
Title: Halo Kinematics of Disk Galaxies beyond the Local Group
Abstract: The study of the old stellar populations in nearby galaxies complements the high-redshift data, which are limited by surface brightness dimming, resolution and dust. Ongoing surveys of the old populations in the Milky Way are beginning to piece together the story of its formation and early evolution. In this project we are extending our knowledge of old populations in the Milky Way to a sample of nearby, edge-on disk galaxies with a range of Hubble type. Our deep surface photometry of these galaxies has shown that surface photometry alone is not enough to distinguish between populations that formed in quite distinct ways, like thick disk and halo --- kinematical data are needed for these faint old stars. This semester we are asking for 4m time with Mosaic to survey the late-type edge-on galaxies NGC 4244 and NGC 5907 for planetary nebulae (PNe). Subsequent spectroscopy of these PNe will allow us to measure halo kinematics for the first time in disk galaxies outside the Local Group --- much more accurately and efficiently than by using globular cluster kinematics at these distances.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360