Suchergebnisse

We present an overview of a new integral field spectroscopic survey called MaNGA (Mapping Nearby Galaxies at Apache Point Observatory), one of three core programs in the fourth-generation Sloan Digital Sky Survey (SDSS-IV) that began on 2014 July 1. MaNGA will investigate the internal kinematic structure and composition of gas and stars in an unprecedented sample of 10,000 nearby galaxies. We summarize essential characteristics of the instrument and survey design in the context of MaNGA's key science goals and present prototype observations to demonstrate MaNGA's scientific potential. MaNGA employs dithered observations with 17 fiber-bundle integral field units that vary in diameter from 12 '' (19 fibers) to 32 '' (127 fibers). Two dual-channel spectrographs provide simultaneous wavelength coverage over 3600-10300 angstrom at R similar to 2000. With a typical integration time of 3 hr, MaNGA reaches a target r-band signal-to-noise ratio of 4-8 (angstrom(-1) per 2 '' fiber) at 23 AB mag arcsec(-2), which is typical for the outskirts of MaNGA galaxies. Targets are selected with M* greater than or similar to 10(9) M-circle dot using SDSS-I redshifts and i-band luminosity to achieve uniform radial coverage in terms of the effective radius, an approximately flat distribution in stellar mass, and a sample spanning a wide range of environments. Analysis of our prototype observations demonstrates MaNGA's ability to probe gas ionization, shed light on recent star formation and quenching, enable dynamical modeling, decompose constituent components, and map the composition of stellar populations. MaNGA's spatially resolved spectra will enable an unprecedented study of the astrophysics of nearby galaxies in the coming 6 yr. ; Alfred P. Sloan Foundation ; National Science Foundation ; U.S. Department of Energy Office of Science ; Carnegie Mellon University ; Colorado University ; Boulder ; Harvard-Smithsonian Center for Astrophysics Participation Group ; Johns Hopkins University ; Kavli Institute for the Physics and Mathematics of the Universe ; Max-Planck-Institut fuer Astrophysik (MPA Garching) ; Max-Planck-Institut fuer Extraterrestrische Physik (MPE) ; Max-Planck-Institut fuer Astronomic (MPIA Heidelberg) ; National Astronomical Observatories of China ; New Mexico State University ; New York University ; Ohio State University ; Penn State University ; Shanghai Astronomical Observatory ; United Kingdom Participation Group ; University of Portsmouth ; University of Utah ; University of Wisconsin ; Yale University ; World Premier International Research Center Initiative (WPI Initiative), MEXT, Japan ; People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7 under REA PITN-GA-2011-289313 ; Strategic Priority Research Program "The Emergence of Cosmological Structures" of the Chinese Academy of Sciences Xdb09000000 ; National Natural Science Foundation of China (NSFC) 11333003 ; Royal Society University Research Fellowship ; Sloan Foundation ; Packard Foundation ; Grainger Foundation ; McDonald Observatory