Publication Date
2009
Abstract
We present a compelling case for a systematic and comprehensive study of the resolved and unresolved stellar populations, ISM, and immediate environments of galaxies throughout the local volume, defined here as D < 20 Mpc. This volume is our cosmic backyard and the smallest volume that encompasses environments as different as the Virgo, Ursa Major, Fornax and (perhaps) Eridanus clusters of galaxies, a large number and variety of galaxy groups, and several cosmic void regions. In each galaxy, through a pan-chromatic (160--1100nm) set of broad-band and diagnostic narrow-band filters, ISM structures and individual luminous stars to >~1 mag below the TRGB should be resolved on scales of <5 pc (at D <~ 20 Mpc, lambda ~ 800nm, for mu_I >~ 24 mag/arcsec^2 and m_{I,TRGB} <~ 27.5 mag). Resolved and unresolved stellar populations would be analyzed through color-magnitude and color-color diagram fitting and population synthesis modeling of multi-band colors and would yield physical properties such as spatially resolved star formation histories. The ISM within and around each galaxy would be analyzed using key narrow-band filters that distinguish photospheric from shock heating and provide information on the metallicity of the gas. Such a study would finally allow unraveling the global and spatially resolved star formation histories of galaxies, their assembly, satellite systems, and the dependences thereof on local and global environment within a truly representative cosmic volume. The proposed study is not feasible with current instrumentation but argues for a wide-field (>~250 arcmin^2), high-resolution (<~0.020"--0.065" [300--1000nm]), ultraviolet--near-infrared imaging facility on a 4m-class space-based observatory.
Recommended Citation
Jansen, Rolf A.; Scowen, Paul; Beasley, Matthew; Gallagher, John; O'Connell, Robert; Calzetti, Daniela; Oey, Sally; Windhorst, Rogier; and Woodruff, Robert, "A Systematic Study of the Stellar Populations and ISM in Galaxies out to the Virgo Cluster: near field cosmology within a representative slice of the local universe" (2009). Astronomy Department Faculty Publication Series. 20.
Retrieved from https://scholarworks.umass.edu/astro_faculty_pubs/20
Comments
This paper was harvested from ArXiv.org and ArXiv identifier is arXiv:0904.2021v1