Browsing by Author "Thomas, D."

Now showing items 1-18 of 18

    • Destruction of molecular gas reservoirs in early-type galaxies by active galactic nucleus feedback 

      Schawinski, K.; Lintott, C.J.; Kaviraj, S.; Silk, J.; Zuntz, J.; Bayet, E.; Thomas, D.; Maraston, C.; Viti, S.; Sarzi, M.; Yi, S.K.; Joo, S-J.; Daddi, E.; Bell, T. (2009)
      Residual star formation at late times in early-type galaxies and their progenitors must be suppressed in order to explain the population of red, passively evolving systems we see today. Likewise, residual or newly accreted ...

    • Environment and self-regulation in galaxy formation 

      Thomas, D.; Maraston, C.; Schawinski, K.; Sarzi, M.; Silk, J. (2010)
      The environment is known to affect the formation and evolution of galaxies considerably best visible through the well-known morphology–density relationship. It is less clear, though, whether the environment is equally ...

    • Environment and the epochs of galaxy formation in the SDSS era 

      Thomas, D.; Maraston, C.; Schawinski, K.; Joo, S.-J.; Kaviraj, S.; Sarzi, M.; Yi, S.K. (2006-12-01)
      We analyse a sample of 1,652 elliptical galaxies morphologically selected from the SDSS DR4 with respect to their stellar population properties such as luminosity weighted ages, metallicities and /Fe element abundance ...

    • Galaxy and Mass Assembly (GAMA): survey diagnostics and core data release 

      Driver, S. P.; Hill, D. T.; Kelvin, L. S.; Robotham, A. S. G.; Liske, J.; Norberg, P.; Baldry, I.K.; Bamford, S. P.; Hopkins, A. M.; Loveday, J.; Peacock, J.A.; Andrae, E.; Bland-Hawthorn, J.; Brough, S.; Brown, M. J. I.; Cameron, E.; Ching, J. H. Y.; Colless, M.; Conselice, C. J.; Croom, S. M.; Cross, N.J.G.; De Propris, R.; Dye, S.; Drinkwater, M. J.; Ellis, S.; Graham, Alister W.; Grootes, M. W.; Gunawardhana, M.; Jones, D. H.; van Kampen, E.; Maraston, C.; Nichol, R.C.; Parkinson, H. R.; Phillipps, S.; Pimbblet, K.; Popescu, C. C.; Prescott, M.; Roseboom, I.G.; Sadler, E.M.; Sansom, A. E.; Sharp, R.G.; Smith, Daniel; Taylor, E.; Thomas, D.; Tuffs, R. J.; Wijesinghe, D.; Dunne, L.; Frenk, C. S.; Jarvis, M.J.; Madore, B. F.; Meyer, M. J.; Seibert, M.; Staveley-Smith, L.; Sutherland, W. J.; Warren, S.J. (2011-05)
      The Galaxy and Mass Assembly (GAMA) survey has been operating since 2008 February on the 3.9-m Anglo-Australian Telescope using the AAOmega fibre-fed spectrograph facility to acquire spectra with a resolution of R approximate ...

    • Galaxy zoo 2 : Detailed morphological classifications for 304,122 galaxies from the sloan digital sky survey 

      Willett, K.W.; Lintott, C.J.; Bamford, S.P.; Masters, K.L.; Simmons, B.D.; Casteels, K.R.V.; Edmondson, E.M.; Fortson, L.F.; Kaviraj, S.; Keel, W.C.; Melvin, T.; Nichol, R.C.; Jordan Raddick, M.; Schawinski, K.; Simpson, R.J.; Skibba, R.A.; Smith, A.M.; Thomas, D. (2013-11-01)
      We present the data release for Galaxy Zoo 2 (GZ2), a citizen science project with more than 16 million morphological classifications of 304,122 galaxies drawn from the Sloan Digital Sky Survey (SDSS).Morphology is a ...

    • Galaxy Zoo : Building the low-mass end of the red sequence with local post-starburst galaxies 

      Wong, O.I.; Schawinski, K.; Kaviraj, S.; Lintott, C.; Darg, D.; Masters, K.L.; Nichol, R.C.; Thomas, D.; Keel, W.C.; Bamford, S.P.; Andreescu, D.; Murray, P.; Raddick, M.J.; Szalay, A.; Vandenberg, J. (2012-02-01)
      We present a study of local post-starburst galaxies (PSGs) using the photometric and spectroscopic observations from the Sloan Digital Sky Survey and the results from the Galaxy Zoo project. We find that the majority of ...

    • Galaxy zoo : The fundamentally different co-evolution of supermassive black holes and their early- and late-type host galaxies 

      Schawinski, K.; Urry, C.M.; Virani, S.; Coppi, P.; Cardamone, C.N.; Bamford, S.P.; Treister, E.; Lintott, C.J.; Kaviraj, S.; Sarzi, M.; Keel, W.C.; Masters, K.L.; Nichol, R.C.; Thomas, D.; Ross, N.P.; Andreescu, D.; Murray, P.; Raddick, M.J.; Szalay, A.S.; Vandenberg, J.; Slosar, A. (2010-01-01)
      We use data from the Sloan Digital Sky Survey and visual classifications of morphology from the Galaxy Zoo project to study black hole growth in the nearby universe (z <0.05) and to break down the active galactic nucleus ...

    • Galaxy Zoo Green Peas: discovery of a class of compact extremely star-forming galaxies 

      Cardamone, C.; Schawinski, K.; Sarzi, M.; Bamford, S.; Bennert, N.; Urry, C.M.; Lintott, C.; Keel, W.; Parejko, J.; Nichol, R.C.; Thomas, D.; Andreescu, D.; Murray, P.; Raddick, M.J.; Slosar, A.; Szalay, A.; Vandenberg, J. (2009)
      We investigate a class of rapidly growing emission line galaxies, known as 'Green Peas', first noted by volunteers in the Galaxy Zoo project because of their peculiar bright green colour and small size, unresolved in Sloan ...

    • Galaxy Zoo: a sample of blue early-type galaxies at low redshift 

      Schawinski, K.; Lintott, C.; Kaviraj, S.; Khochfar, S.; Land, K.; Thomas, D.; Bamford, S. P.; Nichol, R.C.; Sarzi, M.; Andreescu, D.; Murray, P.; Raddick, M.J.; Szalay, A.; Vandenberg, J.; Slosar, A.; Yi, S.K. (2009)
      We report the discovery of a population of nearby, blue early-type galaxies with high star formation rates (0.5 < SFR < 50 M⊙ yr−1) . They are identified by their visual morphology as provided by Galaxy Zoo for Sloan Digital ...

    • Galaxy Zoo: Hanny's Voorwerp, a quasar light echo? 

      Lintott, C.; Schawinski, K.; Keel, W.; Van Arkel, H.; Bennert, N.; Edmondson, E.; Thomas, D.; Smith, Daniel; Herbert, P.D.; Jarvis, M.J.; Virani, S.; Andreescu, D.; Bamford, S.; Land, K.; Murray, P.; Nichol, R.C.; Raddick, M.J.; Slosar, A.; Szalay, A.; Vandenberg, J. (2009)
      We report the discovery of an unusual object near the spiral galaxy IC 2497, discovered by visual inspection of the Sloan Digital Sky Survey (SDSS) as part of the Galaxy Zoo project. The object, known as Hanny's Voorwerp, ...

    • Galaxy Zoo: the fraction of merging galaxies in the SDSS and their morphologies 

      Darg, D.W.; Kaviraj, S.; Lintott, C.J.; Silk, J.; Schawinski, K.; Sarzi, M.; Bamford, S.; Proctor, R.; Andreescu, D.; Murray, P.; Nichol, R.C.; Thomas, D.; Raddick, M.J.; Szalay, A.S.; Vandenberg, J.; Slosar, A. (2010)
      We present the largest, most homogeneous catalogue of merging galaxies in the nearby Universe obtained through the Galaxy Zoo project – an interface on the World Wide Web enabling large-scale morphological classification ...

    • Galaxy Zoo: the fundamentally different co-evolution of supermassive black holes and their early- and late-type host galaxies 

      Schawinski, K.; Urry, C.M.; Virani, S.; Coppi, P.; Bamford, S.; Treister, E.; Lintott, C.; Sarzi, M.; Keel, W.; Kaviraj, S.; Cardamone, C.; Masters, K.L.; Ross, N.P.; Andreescu, D.; Murray, P.; Nichol, R.C.; Raddick, M.J.; Slosar, A.; Szalay, A.; Thomas, D.; Vandenberg, J. (2010)
      We use data from the Sloan Digital Sky Survey and visual classifications of morphology from the Galaxy Zoo project to study black hole growth in the nearby universe (z < 0.05) and to break down the active galactic nucleus ...

    • Galaxy Zoo: The properties of merging galaxies in the nearby Universe - Local environments, colours, masses, star formation rates and AGN activity 

      Darg, D.W.; Kaviraj, S.; Lintott, C.J.; Silk, J.; Schawinski, K.; Sarzi, M.; Bamford, S.; Andreescu, D.; Murray, P.; Nichol, R.C.; Thomas, D.; Raddick, M.J.; Szalay, A.S.; Vandenberg, J.; Slosar, A. (2010)
      Following the study of Darg et al., we explore the environments, optical colours, stellar masses, star formation and active galactic nucleus activity in a sample of 3003 pairs of merging galaxies drawn from the Sloan Digital ...

    • GALICS II : The [ α/Fe]-mass relation in elliptical galaxies 

      Pipino, A.; Devriendt, J.E.G.; Silk, J.; Kaviraj, S.; Thomas, D. (2009-10-03)
      Aims. We test whether the mass-and σ-[α/Fe] relations in the stellar populations of early-type galaxies can be reproduced by a cosmologically motivated assembly history for spheroids.Methods. We implement a detailed treatment ...

    • GAMA/H-ATLAS: the ultraviolet spectral slope and obscuration in galaxies 

      Wijesinghe, D. B.; da Cunha, E.; Hopkins, A. M.; Dunne, L.; Sharp, R.; Gunawardhana, M.; Brough, S.; Sadler, E.M.; Driver, S.; Baldry, I.; Bamford, S.; Liske, J.; Loveday, J.; Norberg, P.; Peacock, J.; Popescu, C. C.; Tuffs, R.; Andrae, E.; Auld, R.; Baes, M.; Bland-Hawthorn, J.; Buttiglione, S.; Cava, A.; Cameron, E.; Conselice, C. J.; Cooray, A.; Croom, S.; Dariush, A.; DeZotti, G.; Dye, S.; Eales, S.; Frenk, C.; Fritz, J.; Hill, D.; Hopwood, R.; Ibar, E.; Ivison, R.; Jarvis, M.J.; Jones, D. H.; van Kampen, E.; Kelvin, L.; Kuijken, K.; Maddox, S. J.; Madore, B.; Michalowski, M. J.; Nichol, B.; Parkinson, H.; Pascale, E.; Pimbblet, K. A.; Pohlen, M.; Prescott, M.; Rhodighiero, G.; Robotham, A. S. G.; Rigby, E. E.; Seibert, M.; Sergeant, S.; Smith, Daniel; Temi, P.; Sutherland, W.; Taylor, E.; Thomas, D.; van der Werf, P. (2011-08)
      We use multiwavelength data from the Galaxy And Mass Assembly (GAMA) and Herschel-ATLAS (H-ATLAS) surveys to compare the relationship between various dust obscuration measures in galaxies. We explore the connections between ...

    • Herschel-ATLAS/GAMA: A difference between star formation rates in strong-line and weak-line radio galaxies 

      Hardcastle, M.J.; Jarvis, M.J.; Mauch, T.; Smith, Daniel; Stevens, J.A.; Ching, J. H. Y.; Croom, S. M.; Sadler, E.M.; Virdee, J.S.; Baes, M.; Baldry, Ivan K.; Brough, S.; Cooray, A.; Dariush, A.; Hopwood, R.; de Zotti, G.; Driver, S.; Robotham, A. S. G.; Dunne, L.; Maddox, S.; Dye, S.; Eales, S.; Valiante, E.; Liske, J.; Michałowski, M. J.; Rigby, E.E.; Steele, O.; Thomas, D. (2013-03)
      We have constructed a sample of radio-loud objects with optical spectroscopy from the Galaxy and Mass Assembly (GAMA) project over the Herschel Astrophysical Terahertz Large Area Survey (Herschel-ATLAS) Phase 1 fields. ...

    • Observational evidence for AGN feedback in early-type galaxies 

      Schawinski, K.; Thomas, D.; Sarzi, M.; Maraston, C.; Kaviraj, S.; Silk, J.; Joo, S-J.; Yi, S.K. (2007)
      A major amendment in recent models of hierarchical galaxy formation is the inclusion of so-called active galactic nucleus (AGN) feedback. The energy input from an active central massive black hole is invoked to suppress ...

    • A Survey of Low Surface Brightness Dwarf Galaxies to Detect H i-rich Companions 

      Taylor, C.L.; Thomas, D.; Brinks, E.; Skillman, E.D. (1996)
      We have conducted a survey for H I-rich companions in the vicinity of low surface brightness (LSB) dwarf galaxies, objects that are characterized by low rates of massive star formation. This survey complements our earlier ...