A study of central galaxy rotation with stellar mass and environment

© 2017. The American Astronomical Society. All rights reserved. We present a pilot analysis of the influence of galaxy stellar mass and cluster environment on the probability of slow rotation in 22 central galaxies at mean redshift z = 0.07. This includes new integral-field observations of five central galaxies selected from the Sloan Digital Sky Survey, observed with the SPIRAL integral-field spectrograph on the Anglo-Australian Telescope. The composite sample presented here spans a wide range of stellar masses, 10.9 < log(M∗/M⊙)lt; 12.0, and are embedded in halos ranging from groups to clusters, 12.9 < log(M 200 Ṁ) < 15.6. We find a mean probability of slow rotation in our sample of P(SR) = 54 ± 7%. Our results show an increasing probability of slow rotation in central galaxies with increasing stellar mass. However, when we examine the dependence of slow rotation on host cluster halo mass, we do not see a significant relationship. We also explore the influence of cluster dominance on slow rotation in central galaxies. Clusters with low dominance are associated with dynamically younger systems. We find that cluster dominance has no significant effect on the probability of slow rotation in central galaxies. These results conflict with a paradigm in which halo mass alone predetermines central galaxy properties

Galaxy And Mass Assembly (GAMA): The mechanisms for quiescent galaxy formation at z < 1

One key problem in astrophysics is understanding how and why galaxies switch off their star formation, building the quiescent population that we observe in the local Universe. From the Galaxy And Mass Assembly and VIsible MultiObject Spectrograph Public Extragalactic Redshift surveys, we use spectroscopic indices to select quiescent and candidate transition galaxies.We identify potentially rapidly transitioning post-starburst (PSB) galaxies and slower transitioning green-valley galaxies. Over the last 8Gyr, the quiescent population has grown more slowly in number density at high masses (M* > 1011M⊙) than at intermediate masses (M* > 1010.6M⊙). There is evolution in both the PSB and green-valley stellar mass functions, consistent with higher mass galaxies quenching at earlier cosmic times.At intermediatemasses (M* > 1010.6M⊙), we find a green-valley transition time-scale of 2.6 Gyr. Alternatively, at z ~ 0.7, the entire growth rate could be explained by fast-quenching PSB galaxies, with a visibility time-scale of 0.5 Gyr. At lower redshift, the number density of PSBs is so low that an unphysically short visibility window would be required for them to contribute significantly to the quiescent population growth. The importance of the fast-quenching route may rapidly diminish at z 1011M⊙), there is tension between the large number of candidate transition galaxies compared to the slow growth of the quiescent population. This could be resolved if not all high-mass PSB and green-valley galaxies are transitioning from star forming to quiescent, for example if they rejuvenate out of the quiescent population following the accretion of gas and triggering of star formation, or if they fail to completely quench their star formationVW and KR acknowledge support from the European Research Council Starting Grant SEDmorph (PI: VW). GAMA is a joint EuropeanAustralasian project based around a spectroscopic campaign using the Anglo-Australian Telescope. The GAMA input catalogue is based on data taken from the SDSS and the UKIRT Infrared Deep Sky Survey. Complementary imaging of the GAMA regions is being obtained by a number of independent survey programs including GALEX MIS, VST KIDS, VISTA VIKING, WISE, Herschel-ATLAS, GMRT and ASKAP providing UV to radio coverage. GAMA is funded by the STFC (UK), the ARC (Australia), the AAO and the participating institutions. The GAMA website is http://www.gama-survey.org/. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 179.A-2004. This paper uses data from the VIMOS Public Extragalactic Redshift Survey (VIPERS). VIPERS has been performed using the ESO Very Large Telescope, under the ‘Large Programme’ 182.A-0886. The participating institutions and funding agencies are listed at http://vipers.inaf.it This research has made use of NASA’s Astrophysics Data System Bibliographic Services

Large Synoptic Survey Telescope Galaxies Science Roadmap

The Large Synoptic Survey Telescope (LSST) will enable revolutionary studies of galaxies, dark matter, and black holes over cosmic time. The LSST Galaxies Science Collaboration has identified a host of preparatory research tasks required to leverage fully the LSST dataset for extragalactic science beyond the study of dark energy. This Galaxies Science Roadmap provides a brief introduction to critical extragalactic science to be conducted ahead of LSST operations, and a detailed list of preparatory science tasks including the motivation, activities, and deliverables associated with each. The Galaxies Science Roadmap will serve as a guiding document for researchers interested in conducting extragalactic science in anticipation of the forthcoming LSST era

A Study of Central Galaxy Rotation With Stellar Mass and Environment

We present a pilot analysis of the influence of galaxy stellar mass and cluster environment on the probability of slow rotation in 22 central galaxies at mean redshift z = 0.07. This includes new integral-field observations of five central galaxies selected from the Sloan Digital Sky Survey, observed with the SPIRAL integral-field spectrograph on the Anglo-Australian Telescope. The composite sample presented here spans a wide range of stellar masses, 10.9 < log( * M M) < 12.0, and are embedded in halos ranging from groups to clusters, 12.9 < log (M M 200 ) < 15.6. We find a mean probability of slow rotation in our sample of P(SR) = 54 7%. Our results show an increasing probability of slow rotation in central galaxies with increasing stellar mass. However, when we examine the dependence of slow rotation on host cluster halo mass, we do not see a significant relationship. We also explore the influence of cluster dominance on slow rotation in central galaxies. Clusters with low dominance are associated with dynamically younger systems. We find that cluster dominance has no significant effect on the probability of slow rotation in central galaxies. These results conflict with a paradigm in which halo mass alone predetermines central galaxy properties.P.O.A. acknowledges the valuable feedback of Chris Lidman, Luca Cortese, and Edoardo Tescari, as well as the ARC Discovery Project DP130101460. S.B. acknowledges funding support from the Australian Research Council through a Future Fellowship (FT140101166) MALL acknowledges support from UNAM through the PAPIIT project IA101315 Funding for the Sloan Digital Sky Survey (SDSS) has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Aeronautics and Space Administration, the National Science Foundation, the U.S. Department of Energy, the Japanese Monbukagakusho, and the Max Planck Society. The SDSS Web site is http://www.sdss.org/

Galaxy And Mass Assembly: The evolution of the cosmic spectral energy distribution from z = 1 to z = 0

We present the evolution of the cosmic spectral energy distribution (CSED) from z = 1 to 0. Our CSEDs originate from stacking individual spectral energy distribution (SED) fits based on panchromatic photometry from the Galaxy And Mass Assembly (GAMA) and COSMOS data sets in 10 redshift intervals with completeness corrections applied. Below z = 0.45, we have credible SED fits from 100 nm to 1 mm. Due to the relatively low sensitivity of the far-infrared data, our far-infrared CSEDs contain a mix of predicted and measured fluxes above z = 0.45. Our results include appropriate errors to highlight the impact of these corrections. We show that the bolometric energy output of the Universe has declined by a factor of roughly 4 – from 5.1 ± 1.0 at z ∼ 1 to 1.3 ± 0.3 × 1035 h70 W Mpc−3 at the current epoch. We show that this decrease is robust to cosmic sample variance, the SED modelling and other various types of error. Our CSEDs are also consistent with an increase in the mean age of stellar populations. We also show that dust attenuation has decreased over the same period, with the photon escape fraction at 150 nm increasing from 16 ± 3 at z ∼ 1 to 24 ± 5 per cent at the current epoch, equivalent to a decrease in AFUV of 0.4 mag. Our CSEDs account for 68 ± 12 and 61 ± 13 per cent of the cosmic optical and infrared backgrounds, respectively, as defined from integrated galaxy counts and are consistent with previous estimates of the cosmic infrared background with redshift