Browsing by Author "Dye, S."
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- ItemA detailed gravitational lens model based on submillimeter array and keck adaptive optics imaging of a Herschel-atlas submillimeter galaxy AT z = 4.243.(2012) Bussmann, R. S.; Kim, Sam; Gurwell, M. A.; Fu, Hai; Smith, D. J. B.; Dye, S.; Auld, R.; Baes, M.; Baker, A. J.; Bonfield, D.; Cava, A.
- ItemCOSMOGRAIL : the COSmological MOnitoring of GRAvItational Lenses.(2006) Saha, P.; Courbin, F.; Sluse, D.; Dye, S.; Meylan, G.
- ItemFar-infrared spectroscopy of a lensed starburst: a blind redshift from Herschel(2013) George, R. D.; Ivison, R. J.; Hopwood, R.; Riechers, D. A.; Bussmann, R. S.; Cox, P.; Dye, S.; Krips, M.; Negrello, M.; Neri, R.; Serjeant, S.; Valtchanov, I.; Baes, M.; Bourne, N.; Clements, D. L.; De Zotti, G.; Dunne, L.; Eales, S. A.; Ibar, E.; Maddox, S.; Smith, M. W. L.; Valiante, E.; van der Werf, P.We report the redshift of HATLAS J132427.0+284452 (hereafter HATLAS J132427), a gravitationally lensed starburst galaxy, the first determined 'blind' by the Herschel Space Observatory. This is achieved via the detection of [C II] consistent with z = 1.68 in a far-infrared spectrum taken with the SPIRE Fourier Transform Spectrometer (FTS). We demonstrate that the [C II] redshift is secure via detections of CO J = 2 -> 1 and 3 -> 2 using the Combined Array for Research in Millimeter-wave Astronomy and the Institut de Radioastronomie Millimetrique's Plateau de Bure Interferometer. The intrinsic properties appear typical of high-redshift starbursts despite the high lensing-amplified fluxes, proving the ability of the FTS to probe this population with the aid of lensing. The blind detection of [C II] demonstrates the potential of the SPICA Far-infrared Instrument imaging spectrometer, proposed for the much more sensitive Space Infrared Telescope for Cosmology and Astrophysics mission, to determine redshifts of multiple dusty galaxies simultaneously without the benefit of lensing.
- ItemGRAVITATIONAL LENS MODELS BASED ON SUBMILLIMETER ARRAY IMAGING OF HERSCHEL-SELECTED STRONGLY LENSED SUB-MILLIMETER GALAXIES AT z > 1.5(2013) Bussmann, R. S.; Perez-Fournon, I.; Amber, S.; Calanog, J.; Gurwell, M. A.; Dannerbauer, H.; De Bernardis, F.; Fu, Hai; Harris, A. I.; Krips, M.; Lapi, A.; Maiolino, R.; Omont, A.; Riechers, D.; Wardlow, J.; Baker, A. J.; Birkinshaw, M.; Bock, J.; Bourne, N.; Clements, D. L.; Cooray, A.; De Zotti, G.; Dunne, L.; Dye, S.; Eales, S.; Farrah, D.; Gavazzi, R.; Nuevo, J. Gonzalez; Hopwood, R.; Ibar, E.; Ivison, R. J.; Laporte, N.; Maddox, S.; Martinez-Navajas, P.; Michalowski, M.; Negrello, M.; Oliver, S. J.; Roseboom, I. G.; Scott, Douglas; Serjeant, S.; Smith, A. J.; Smith, Matthew; Streblyanska, A.; Valiante, E.; van der Werf, P.; Verma, A.; Vieira, J. D.; Wang, L.; Wilner, D.Strong gravitational lenses are now being routinely discovered in wide-field surveys at (sub-)millimeter wavelengths. We present Submillimeter Array (SMA) high-spatial resolution imaging and Gemini-South and Multiple Mirror Telescope optical spectroscopy of strong lens candidates discovered in the two widest extragalactic surveys conducted by the Herschel Space Observatory: the Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS) and the Herschel Multi-tiered Extragalactic Survey (HerMES). From a sample of 30 Herschel sources with S-500 > 100 mJy, 21 are strongly lensed (i.e., multiply imaged), 4 are moderately lensed (i.e., singly imaged), and the remainder require additional data to determine their lensing status. We apply a visibility-plane lens modeling technique to the SMA data to recover information about the masses of the lenses as well as the intrinsic (i.e., unlensed) sizes (r(half)) and far-infrared luminosities (L-FIR) of the lensed submillimeter galaxies (SMGs). The sample of lenses comprises primarily isolated massive galaxies, but includes some groups and clusters as well. Several of the lenses are located at z(lens) > 0.7, a redshift regime that is inaccessible to lens searches based on Sloan Digital Sky Survey spectroscopy. The lensed SMGs are amplified by factors that are significantly below statistical model predictions given the 500 mu m flux densities of our sample. We speculate that this may reflect a deficiency in our understanding of the intrinsic sizes and luminosities of the brightest SMGs. The lensed SMGs span nearly one decade in L-FIR (median L-FIR = 7.9 x 10(12) L-circle dot) and two decades in FIR luminosity surface density (median Sigma(FIR) = 6.0 x 10(11) L-circle dot kpc(-2)). The strong lenses in this sample and others identified via (sub-) mm surveys will provide a wealth of information regarding the astrophysics of galaxy formation and evolution over a wide range in redshift.
- ItemH2O emission in high-z ultra-luminous infrared galaxies(2013) Omont, A.; Yang, C.; Cox, P.; Neri, R.; Beelen, A.; Bussmann, R. S.; Gavazzi, R.; van der Werf, P.; Riechers, D.; Downes, D.; Krips, M.; Dye, S.; Ivison, R.; Vieira, J. D.; Weiss, A.; Aguirre, J. E.; Baes, M.; Baker, A. J.; Bertoldi, F.; Cooray, A.; Dannerbauer, H.; De Zotti, G.; Eales, S. A.; Fu, H.; Gao, Y.; Guelin, M.; Harris, A. I.; Jarvis, M.; Lehnert, M.; Leeuw, L.; Lupu, R.; Menten, K.; Michalowski, M. J.; Negrello, M.; Serjeant, S.; Temi, P.; Auld, R.; Dariush, A.; Dunne, L.; Fritz, J.; Hopwood, R.; Hoyos, C.; Ibar, E.; Maddox, S.; Smith, M. W. L.; Valiante, E.; Bock, J.; Bradford, C. M.; Glenn, J.; Scott, K. S.Using the IRAM Plateau de Bure interferometer (PdBI), we report the detection of water vapor in six new lensed ultra-luminous starburst galaxies at high redshift, discovered in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). The sources are detected either in the 2(02)-1(11) or 2(11)-2(02) H2O emission lines with integrated line fluxes ranging from 1.8 to 14 Jy km s(-1). The corresponding apparent luminosities are mu L-H2O similar to 3-12 x 10(8) L-circle dot, where mu is the lensing magnification factor (3 < mu < 12). These results confirm that H2O lines are among the strongest molecular lines in high-z ultra-luminous starburst galaxies, with intensities almost comparable to those of the high-J CO lines, and similar profiles and line widths (similar to 200-900 km s(-1)). With the current sensitivity of the PdBI, the water lines can therefore easily be detected in high-z lensed galaxies (with F(500 mu m) > 100 mJy) discovered in the Herschel surveys. Correcting the luminosities for amplification, using existing lensing models, L-H2O is found to have a strong dependence on the infrared luminosity, varying as similar to L-IR(1.2). This relation, which needs to be confirmed with better statistics, may indicate a role of radiative (infrared) excitation of the H2O lines, and implies that high-z galaxies with L-IR greater than or similar to 10(13) L-circle dot tend to be very strong emitters in water vapor, that have no equivalent in the local universe.
- ItemHerschel-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
- ItemHerschel-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)].
- ItemHerschel-ATLAS: modelling the first strong gravitational lenses(2014) Dye, S.; Negrello, M.; Hopwood, R.; Nightingale, J. W.; Bussmann, R. S.; Amber, S.; Bourne, N.; Cooray, A.; Dariush, A.; Dunne, L.; Eales, S. A.; Gonzalez-Nuevo, J.; Ibar, E.; Ivison, R. J.; Maddox, S.; Valiante, E.; Smith, M.We have determined the mass density radial profiles of the first five strong gravitational lens systems discovered by the Herschel Astrophysical Terahertz Large Area Survey. We present an enhancement of the semilinear lens inversion method of Warren & Dye which allows simultaneous reconstruction of several different wavebands and apply this to dual-band imaging of the lenses acquired with the Hubble Space Telescope. The five systems analysed here have lens redshifts which span a range 0.22 <= z <= 0.94. Our findings are consistent with other studies by concluding that: (1) the logarithmic slope of the total mass density profile steepens with decreasing redshift; (2) the slope is positively correlated with the average total projected mass density of the lens contained within half the effective radius and negatively correlated with the effective radius; (3) the fraction of dark matter contained within half the effective radius increases with increasing effective radius and increases with redshift.