Integral field spectroscopy of a sample of nearby galaxies I. Sample, observations, and data reduction

© ESO, 2011. We thank the referee, Matt Bershady, for his useful comments. We acknowledge the Viabilidad, Diseño, Acceso y Mejora funding program, ICTS-2009-10, and the Plan Nacional de Investigación y Desarrollo funding program AYA2010-22111-C03-03 and AYA-2010-10904-E, of the Spanish Ministerio de Ciencia e Innovación (MICINN), for the support given to this project. E.M.Q. acknowledges financial support from the research projects AYA2007-67752-C03-03 and AYA2010-21322-C03-02. E.M.Q., R.M. and A.G.P. thank support from Consolider-GTC and AstroMadrid S2009/ESP-1496 - from the Comunidad de Madrid -. R.M. and A.G.P. acknowledge financial support from the project AYA2005-09413-C02-02. J.V.M. and J.I.P. are funded by the grants AYA2007-67965-C03-02 - from the Spanish MICINN and TIC114 - from the Junta de Andalucía -. We also thank the director of CEFCA, Dr. M. Moles, for his sincere support of this project. This paper makes use of the Sloan Digital Sky Survey data. Funding for the SDSS and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the US Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England. The SDSS Web Site is http://www.sdss.org/. The SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions. The Participating Institutions are the American Museum of Natural History, Astrophysical Institute Potsdam, University of Basel, University of Cambridge, Case Western Reserve University, University of Chicago, Drexel University, Fermilab, the Institute for Advanced Study, the Japan Participation Group, Johns Hopkins University, the Joint Institute for Nuclear Astrophysics, the Kavli Institute for Particle Astrophysics and Cosmology, the Korean Scientist Group, the Chinese Academy of Sciences (LAMOST), Los Alamos National Laboratory, the Max
Aims. Integral field spectroscopy (IFS) is a powerful approach to studying nearby galaxies since it enables a detailed analysis of their resolved physical properties. Here we present our study of a sample of nearby galaxies selected to exploit the two-dimensional information provided by the IFS. Methods. We observed a sample of 48 galaxies from the local universe with the PPaK integral field spectroscopy unit (IFU), of the PMAS spectrograph, mounted at the 3.5 m telescope at Calar Alto Observatory (Almeria, Spain). Two different setups were used during these studies (low – V300 – and medium – V600 – resolution mode) covering a spectral range of around 3700–7000 ÅÅ. We developed a full automatic pipeline for the data reduction, which includes an analysis of the quality of the final data products. We applied a decoupling method to obtain the ionised gas and stellar content of these galaxies, and derive the main physical properties of the galaxies. To assess the accuracy in the measurements of the different parameters, we performed a set of simulations to derive the expected relative errors obtained with these data. In addition, we extracted spectra for two types of aperture, one central and another integrated over the entire galaxy, from the datacubes. The main properties of the stellar populations and ionised gas of these galaxies and an estimate of their relative errors are derived from those spectra, as well as from the whole datacubes. Results. We compare the central spectrum extracted from our datacubes and the SDSS spectrum for each of the galaxies for which this is possible, and find close agreement between the derived values for both samples. We find differences on the properties of galaxies when comparing a central and an integrated spectra, showing the effects of the extracted aperture on the interpretation of the data. Finally, we present two-dimensional maps of some of the main properties derived with the decoupling procedure.
Comunidad de Madrid
Ministerio de Ciencia e Innovación (MICINN)
Junta de Andalucia
Alfred P. Sloan Foundation
National Science Foundation
US Department of Energy
National Aeronautics and Space Administration (NASA)
Japanese Monbukagakusho
Max Planck Society
Higher Education Funding Council for England
Viabilidad, Diseño, Acceso y Mejora funding program
Astrophysical Research Consortium
Depto. de Física de la Tierra y Astrofísica
Fac. de Ciencias Físicas
TRUE
pub