VENGA Maps of NGC 2903
VENGA is an integral field spectroscopic survey which uses the Mitchell Spectrograph (a.k.a VIRUS-P) at the 2.7m Harlan J. Smith Telescope at McDonald Observatory to map the disks of 30 nearby spiral galaxies. Targets span a wide range in Hubble type, star formation activity, morphology, and inclination. The VENGA data-cubes have 5.6'' FWHM spatial resolution, 5 Angstrom FWHM spectral resolution, sample the 3600-6800 Angstrom range, and cover large areas typically sampling galaxies out to ~0.7 R25. These data-cubes can be used to produce 2D maps of the star formation rate, dust extinction, electron density, stellar population parameters, the kinematics and chemical abundances of both stars and ionized gas, and other physical quantities derived from the fitting of the stellar spectrum and the measurement of nebular emission lines.
VENGA will allow a large number of researchers to conduct an extensive set of studies on star-formation, structure assembly, stellar populations, gas and stellar dynamics, chemical evolution, ISM structure, and galactic feedback, which will provide answers to many important questions in galaxy formation and evolution.
In Lambda-CDM cosmology, the formation and subsequent evolution of galaxies takes place in gravitational potential wells in the dark matter distribution (DM halos). Gas accretion into halos and merging processes ultimately trigger star formation giving raise to galaxies. Although consensus has been reached concerning this big picture, the details of the baryonic physics behind galaxy formation in the centers of DM halos are aggressively debated. The triggering of star formation and the variables that set the star formation rate (SFR), the contribution from different types of feedback processes (stellar, AGN, SN) at regulating the gaseous budget, structure and kinematics of the ISM, and the role that major and minor mergers as well as secular evolution processes play at configuring the diverse morphologies observed in galaxies, are the main current areas of research. All these processes play a major role in determining how galaxies evolve throughout cosmic time, building up their stellar mass and shaping their present day structure. Integral field spectroscopy allows us to map the present day structure, dynamics, and chemical composition of both stars and gas within galaxies and can be a powerful tool to study the physical processes that drive galaxy evolution.