Browsing by Author "Khochfar, S."

Now showing items 1-20 of 26

    • Asymmetries in extragalactic double radio sources: clues from 3D simulations of jet-disc interaction 

      Gaibler, V.; Khochfar, S.; Krause, M. (2011-02-11)
      Observational and theoretical studies of extragalactic radio sources have suggested that an inhomogeneous environment may be responsible for observed arm-length asymmetries of jets and the properties of extended emission-line ...

    • The ATLAS 3D project - XI : Dense molecular gas properties of CO-luminous early-type galaxies 

      Crocker, A.; Krips, M.; Bureau, M.; Young, L.M.; Davis, T.A.; Bayet, E.; Alatalo, K.; Blitz, L.; Bois, M.; Bournaud, F.; Cappellari, M.; Davies, R. L.; de Zeeuw, P.T.; Duc, P.A.; Emsellem, E.; Khochfar, S.; Krajnović, D.; Kuntschner, H.; Lablanche, Pierre-Yves; McDermid, Richard M.; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Sarzi, Marc; Scott, N.; Serra, P.; Weijmans, Anne-Marie (2012-04)
      Surveying 18 12CO-bright galaxies from the ATLAS 3D early-type galaxy sample with the Institut de Radio Astronomie Millimétrique (IRAM) 30-m telescope, we detect 13CO(1-0) and 13CO(2-1) in all 18 galaxies, HCN(1-0) in 12/18 ...

    • The ATLAS 3D Project - XXXI. Nuclear radio emission in nearby early-type galaxies 

      Nyland, K.; Young, L.~M.; Wrobel, J.~M.; Sarzi, M.; Morganti, R.; Alatalo, K.; Blitz, L.; Bournaud, F.; Bureau, M.; Cappellari, M.; Crocker, A.~F.; Davies, R.~L.; Davis, Timothy; de Zeeuw, P.~T.; Duc, P.-A.; Emsellem, E.; Khochfar, S.; Krajnovi, D.; Kuntschner, H.; McDermid, R.~M.; Naab, T.; Oosterloo, T.; Scott, N.; Serra, P.; Weijmans, A.-M. (2016-05-11)
      We present the results of a high-resolution, 5 GHz, Karl G. Jansky Very Large Array study of the nuclear radio emission in a representative subset of the ATLAS3D survey of early-type galaxies (ETGs). We find that 51 ± 4 ...

    • The ATLAS project - IX. The merger origin of a fast- and a slow-rotating early-type galaxy revealed with deep optical imaging : First results 

      Duc, P.-A.; Ferriere, E.; Bournaud, F.; Cuillandre, J.-C.; Serra, P.; Morganti, R.; Oosterloo, T.; Michel-Dansac, L.; Bois, M.; Emsellem, E.; Lablanche, P.-Y.; Alatalo, K.; Blitz, L.; Bois, M.; de Zeeuw, P.T.; Emsellem, E.; Krajnović, D.; Bureau, M.; Cappellari, M.; Davies, R.L.; Davis, T.A.; Scott, N.; Khochfar, S.; Kuntschner, H.; McDermid, R.M.; Morganti, R.; Oosterloo, T.; Naab, T.; Sarzi, M.; Weijmans, A.-M.; Young, L.M. (2011-10-01)
      The mass assembly of galaxies leaves imprints in their outskirts, such as shells and tidal tails. The frequency and properties of such fine structures depend on the main acting mechanisms - secular evolution, minor or major ...

    • The ATLAS project - VIII. Modelling the formation and evolution of fast and slow rotator early-type galaxies within ΛCDM 

      Khochfar, S.; Emsellem, E.; Bois, M.; de Zeeuw, P.T.; Krajnović, D.; Emsellem, E.; Bois, M.; Bacon, R.; Lablanche, P.-Y.; Serra, P.; Morganti, R.; Oosterloo, T.; Alatalo, K.; Blitz, L.; Bournaud, F.; Oosterloo, T.; Bureau, M.; Cappellari, M.; Davies, R.L.; Davis, T.A.; Scott, N.; Duc, P.-A.; Kuntschner, H.; McDermid, R.M.; Morganti, R.; Naab, T.; Sarzi, M.; Weijmans, A.-M.; Young, L.M. (2011-10-01)
      We propose a simple model for the origin of fast and slow rotator early-type galaxies (ETG) within the hierarchical Λcold dark matter (ΛCDM) scenario, that is based on the assumption that the mass fraction of stellar discs ...

    • The ATLAS project - X. On the origin of the molecular and ionized gas in early-type galaxies 

      Davis, T.A.; Bureau, M.; Cappellari, M.; Davies, R.L.; Scott, N.; Alatalo, K.; Blitz, L.; Sarzi, M.; Young, L.M.; Serra, P.; Morganti, R.; Oosterloo, T.; Crocker, A.F.; Krajnović, D.; de Zeeuw, P.T.; Emsellem, E.; McDermid, R.M.; Bois, M.; Bournaud, F.; Duc, P.-A.; de Zeeuw, P.T.; Emsellem, E.; Lablanche, P.-Y.; Khochfar, S.; Kuntschner, H.; Morganti, R.; Oosterloo, T.; Naab, T.; Weijmans, A.-M. (2011-10-01)
      We make use of interferometric CO and Hi observations, and optical integral-field spectroscopy from the ATLAS survey, to probe the origin of the molecular and ionized interstellar medium (ISM) in local early-type galaxies. ...

    • The ATLAS3D project - XXV : Two-dimensional kinematic analysis of simulated galaxies and the cosmological origin of fast and slow rotators 

      Naab, Thorsten; Oser, L.; Emsellem, E.; Cappellari, Michele; Krajnović, D.; McDermid, Richard M.; Alatalo, Katherine; Bayet, Estelle; Blitz, L.; Bois, M.; Bournaud, Frederic; Bureau, M.; Crocker, A.; Davies, R. L.; Davis, T. A.; de Zeeuw, P.T.; Duc, P.A.; Hirschmann, Michaela; Johansson, P. H.; Khochfar, S.; Kuntschner, H.; Morganti, R.; Oosterloo, T.; Sarzi, Marc; Scott, N.; Serra, P.; van de Ven, G.; Weijmans, A.; Young, Lisa M. (2014-11-11)
      We present a detailed two-dimensional stellar dynamical analysis of a sample of 44 cosmological hydrodynamical simulations of individual central galaxies with stellar masses of 2 × 1010 M⊙ ≲ M* ≲ 6 × 1011 M⊙. Kinematic ...

    • A census of nuclear stellar discs in early-type galaxies 

      Ledo, H.R.; Sarzi, M.; Dotti, M.; Khochfar, S.; Morelli, L. (2010)
      Nuclear stellar discs (NSDs), of a few tens to hundreds of parsec across, are a common and yet poorly studied feature of early-type galaxies. Still, such small discs represent a powerful tool to constrain the assembling ...

    • Composite star formation histories of early-type galaxies from minor mergers : prospects for WFC3 

      Peirani, S.; Crockett, R.M.; Geen, S.; Kaviraj, S.; Silk, J.; Khochfar, S. (2010-07-01)
      The star formation history of nearby early-type galaxies is investigated via numerical modelling. Idealized hydrodynamical N-body simulations with a star formation prescription are used to study the minor merger process ...

    • A deep ALMA image of the Hubble Ultra Deep Field 

      Dunlop, J. S.; McLure, R. J.; Biggs, A. D.; Geach, J. E.; Michalowski, M. J.; Ivison, R. J.; Rujopakarn, W.; Kampen, E. van; Kirkpatrick, A.; Pope, A.; Scott, D.; Swinbank, A. M.; Targett, T. A.; Aretxaga, I.; Austermann, J. E.; Best, P. N.; Bruce, V. A.; Chapin, E. L.; Charlot, S.; Cirasuolo, M.; Coppin, K. E. K.; Ellis, R. S.; Finkelstein, S. L.; Hayward, C. C.; Hughes, D. H.; Ibar, E.; Khochfar, S.; Koprowski, M. P.; Narayanan, D.; Papovich, C.; Peacock, J. A.; Robertson, B.; Vernstrom, T.; Werf, P. P. van der; Wilson, G. W.; Yun, M. (2017-04-01)
      We present the results of the first, deep ALMA imaging covering the full 4.5 sq arcmin of the Hubble Ultra Deep Field (HUDF) as previously imaged with WFC3/IR on HST. Using a mosaic of 45 pointings, we have obtained a ...

    • Dust attenuation in 2<z<3 star-forming galaxies from deep ALMA observations of the Hubble Ultra Deep Field 

      McLure, R. J.; Dunlop, J. S.; Cullen, F.; Bourne, N.; Best, P. N.; Khochfar, S.; Bowler, R. A. A.; Biggs, A. D.; Geach, J. E.; Scott, D.; Michalowski, M. J.; Rujopakarn, W.; Kampen, E. van; Kirkpatrick, A.; Pope, A. (2018-05-21)
      We present the results of a new study of the relationship between infrared excess (IRX ≡ L IR/L UV), ultraviolet (UV) spectral slope (β) and stellar mass at redshifts 2 < z < 3, based on a deep Atacama Large Millimeter ...

    • The effect of environment on the ultraviolet color-magnitude relation of early-type galaxies 

      Schawinski, K.; Kaviraj, S.; Khochfar, S.; Yoon, S.-J.; Yi, S.K.; Lee, Y.-W.; Deharveng, J.-M.; Boselli, A.; Donas, J.; Milliard, B.; Barlow, T.; Conrow, T.; Forster, K.; Friedman, P.G.; Martin, D.C.; Morrissey, P.; Seibert, M.; Small, T.; Wyder, T.; Neff, S.; Schiminovich, D.; Blanchi, L.; Heckman, T.; Szalay, A.; Madore, B.; Rich, R.M. (2007-12-01)
      We use GALEX near-UV (NUV ) photometry of a sample of early-type galaxies selected in the SDSS (Sloan Digital Sky Survey) to study the UV color-magnitude relation (CMR). NUV - r color is an excellent tracer of even small ...

    • Formation of slowly rotating early-type galaxies via major mergers: a resolution study 

      Bois, M.; Bournaud, F.; Emsellem, E.; Alatalo, K.; Blitz, L.; Bureau, M.; Cappellari, M.; Davies, R.L.; Davis, T.A.; de Zeeuw, P.T.; Duc, P.A.; Khochfar, S.; Krajnovic, D.; Kuntschner, H.; Lablanche, P.-Y.; McDermid, R.M.; Morganti, R.; Naab, T.; Oosterloo, T.; Sarzi, M.; Scott, N.; Serra, P.; Weijmans, A.; Young, L.M. (2010)
      We study resolution effects in numerical simulations of gas-rich and gas-poor major mergers, and show that the formation of slowly rotating elliptical galaxies often requires a resolution that is beyond the present-day ...

    • 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 ...

    • Galex-derived residual star formation history of elliptical galaxies 

      Yi, S.K.; Kaviraj, S.; Schawinski, K.; Khochfar, S. (EDP Sciences, 2007)
      Bright early-type galaxies are still forming stars at low-level residual star formation (RSF) mode. The GALEX UV satellite has detected excessive UV flux in > 30% of our volume-limited sample of ∼10 galaxies. The RSF galaxy ...

    • Investigating the merger origin of early-type galaxies using ultra-deep optical images 

      Duc, P.-A.; Bournaud, F.; Ferriere, E.; Cuillandre, J.-C.; Alatalo, K.; Blitz, L.; Bois, M.; Emsellem, E.; Lablanche, P.-Y.; Michel-Dansac, L.; Bureau, M.; Cappellari, M.; Davies, R.L.; Davis, T.A.; Scott, N.; Côté, P.; Ferrarese, L.; Gwyn, S.; MacArthur, L.; De Zeeuw, P.T.; Krajnovic, D.; Kuntschner, H.; Khochfar, S.; McDermid, R.M.; Morganti, R.; Oosterloo, T.; Serra, P.; Naab, T.; Sarzi, M.; Weijmans, A.; Young, L.M. (2010-12-01)
      The mass assembly of galaxies leaves various imprints on their surroundings, such as shells, streams and tidal tails. The frequency and properties of these fine structures depend on the mechanism driving the mass assembly: ...

    • Jet interactions with a giant molecular cloud in the Galactic centre and ejection of hypervelocity stars 

      Silk, J.; Antonuccio-Delogu, V.; Dubois, Y.; Gaibler, V.; Haas, M.~R.; Khochfar, S.; Krause, Martin (2012-09-21)
      The hypervelocity OB stars in the Milky Way Galaxy were ejected from the central regions some 10-100 million years ago. We argue that these stars, as well as many more abundant bound OB stars in the innermost few parsecs, ...

    • Jet-induced star formation in gas-rich galaxies 

      Gaibler, V.; Khochfar, S.; Krause, M.; Silk, J. (2012-09-01)
      Feedback from active galactic nuclei (AGN) has become a major component in simulations of galaxy evolution, in particular for massive galaxies. AGN jets have been shown to provide a large amount of energy and are capable ...

    • Molecular gas and star formation in local early-type galaxies 

      Bureau, M.; Davis, T.A.; Cappellari, M.; Davies, R.L.; Scott, N.; Alatalo, K.; Blitz, L.; Crocker, A.F.; Young, L.M.; Combes, F.; Bois, M.; Emsellem, E.; Lablanche, P.-Y.; Bournaud, F.; De Zeeuw, P.T.; Krajnović, D.; Kuntschner, H.; Duc, P.-A.; Khochfar, S.; McDermid, R.M.; Morganti, R.; Oosterloo, T.; Serra, P.; Naab, T.; Sarzi, M.; Weijmans, A. (2010-12-01)
      The molecular gas content of local early-type galaxies is constrained and discussed in relation to their evolution. First, as part of the ATLAS survey, we present the first complete, large (260 objects), volume-limited ...

    • Nuclear discs as clocks for the assembly history of early-type galaxies: the case of NGC 4458 

      Sarzi, M.; Ledo, H.~R.; Coccato, L.; Corsini, E.~M.; Dotti, M.; Khochfar, S.; Maraston, C.; Morelli, L.; Pizzella, A. (2016-04-01)
      Approximately 20 per cent of early-type galaxies host small nuclear stellar discs that are tens to a few hundred parsecs in size. Such discs are expected to be easily disrupted during major galactic encounters, hence their ...