Browsing by Author "Rowlands, K."

Now showing 1 - 4 of 4
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    Herschel-ATLAS : deep HST/WFC3 imaging of strongly lensed submillimetre galaxies.
    (2014) Negrello, Mattia; Kim, Sam; Hopwood, R.; Dye, S.; Cunha, E. da; Serjeant, S.; Fritz, J.; Rowlands, K.; Fleuren, S.; Bussmann, R. S.; Cooray, Asantha
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    HERSCHEL-ATLAS: A BINARY HyLIRG PINPOINTING A CLUSTER OF STARBURSTING PROTOELLIPTICALS
    (2013) Ivison, R. J.; Swinbank, A. M.; Smail, Ian; Harris, A. I.; Bussmann, R. S.; Cooray, A.; Cox, P.; Fu, H.; Kovacs, A.; Krips, M.; Narayanan, D.; Negrello, M.; Neri, R.; Penarrubia, J.; Richard, J.; Riechers, D. A.; Rowlands, K.; Staguhn, J. G.; Targett, T. A.; Amber, S.; Baker, A. J.; Bourne, N.; Bertoldi, F.; Bremer, M.; Calanog, J. A.; Clements, D. L.; Dannerbauer, H.; Dariush, A.; De Zotti, G.; Dunne, L.; Eales, S. A.; Farrah, D.; Fleuren, S.; Franceschini, A.; Geach, J. E.; George, R. D.; Helly, J. C.; Hopwood, R.; Ibar, E.; Jarvis, M. J.; Kneib, J. -P.; Maddox, S.; Omont, A.; Scott, D.; Serjeant, S.; Smith, M. W. L.; Thompson, M. A.; Valiante, E.; Valtchanov, I.; Vieira, J.; van der Werf, P.
    Panchromatic observations of the best candidate hyperluminous infrared galaxies from the widest Herschel extragalactic imaging survey have led to the discovery of at least four intrinsically luminous z = 2.41 galaxies across an approximate to 100 kpc region-a cluster of starbursting protoellipticals. Via subarcsecond interferometric imaging we have measured accurate gas and star formation surface densities. The two brightest galaxies span similar to 3 kpc FWHM in submillimeter/radio continuum and CO J = 4-3, and double that in CO J = 1-0. The broad CO line is due partly to the multitude of constituent galaxies and partly to large rotational velocities in two counter-rotating gas disks-a scenario predicted to lead to the most intense starbursts, which will therefore come in pairs. The disks have M-dyn of several x 10(11) M-circle dot, and gas fractions of similar to 40%. Velocity dispersions are modest so the disks are unstable, potentially on scales commensurate with their radii: these galaxies are undergoing extreme bursts of star formation, not confined to their nuclei, at close to the Eddington limit. Their specific star formation rates place them greater than or similar to 5x above the main sequence, which supposedly comprises large gas disks like these. Their high star formation efficiencies are difficult to reconcile with a simple volumetric star formation law. N-body and dark matter simulations suggest that this system is the progenitor of a B(inary)-type approximate to 10(14.6)-M-circle dot cluster.
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    Herschel-ATLAS: correlations between dust and gas in local submm-selected galaxies
    (2013) Bourne, N.; Dunne, L.; Bendo, G. J.; Smith, M. W. L.; Clark, C. J. R.; Smith, D. J. B.; Rigby, E. E.; Baes, M.; Leeuw, L. L.; Maddox, S. J.; Thompson, M. A.; Bremer, M. N.; Cooray, A.; Dariush, A.; de Zotti, G.; Dye, S.; Eales, S.; Hopwood, R.; Ibar, E.; Ivison, R. J.; Jarvis, M. J.; Michalowski, M. J.; Rowlands, K.; Valiante, E.
    We present an analysis of CO molecular gas tracers in a sample of 500 mu m-selected Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) galaxies at z < 0.05 (cz < 14990 km s(-1)). Using 22-500 mu m photometry from Wide-Field Infrared Survey Explorer, Infrared Astronomical Satellite and Herschel, with HI data from the literature, we investigate correlations between warm and cold dust, and tracers of the gas in different phases. The correlation between global CO(3-2) line fluxes and far-infrared (FIR)-submillimetre (submm) fluxes weakens with increasing infrared wavelength (lambda greater than or similar to 60 mu m), as a result of colder dust being less strongly associated with dense gas. Conversely, CO(2-1) and HI line fluxes both appear to be better correlated with longer wavelengths, suggesting that cold dust is more strongly associated with diffuse atomic and molecular gas phases, consistent with it being at least partially heated by radiation from old stellar populations. The increased scatter at long wavelengths implies that submm fluxes are a poorer tracer of star formation rate (SFR). Fluxes at 22 and 60 mu m are also better correlated with diffuse gas tracers than dense CO(3-2), probably due to very small grain emission in the diffuse interstellar medium, which is not correlated with SFR. The FIR/CO luminosity ratio and the dust mass/CO luminosity ratio both decrease with increasing luminosity, as a result of either correlations between mass and metallicity (changing CO/H-2) or between CO luminosity and excitation [changing CO(3-2)/CO(1-0)].
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    SDSS-IV MaNGA : inside-out versus outside-in quenching of galaxies in different local environments
    (2019) Lin, L.W.; Hsieh, B.C.; Pa, H.A.; Rembold, A.B.; Sanchez, S.F.; Argudo Fernandez, M.; Rowlands, K.; Belfiore, F.; Bizyael, D.; Rong, Y.