Browsing by Author "Negrello, Mattia"

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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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    ON THE NATURE OF THE FIRST GALAXIES SELECTED AT 350 mu m
    (IOP PUBLISHING LTD, 2009) Khan, Sophia A.; Chanial, Pierre F.; Willner, S. P.; Pearson, Chris P.; Ashby, M. L. N.; Benford, Dominic J.; Clements, David L.; Dye, Simon; Farrah, Duncan; Fazio, G. G.; Huang, J. S.; Lebouteiller, V.; Le Floc'h, Emeric; Mainetti, Gabriele; Moseley, S. Harvey; Negrello, Mattia; Serjeant, Stephen; Shafer, Richard A.; Staguhn, Johannes; Sumner, Timothy J.; Vaccari, Mattia
    We present constraints on the nature of the first galaxies selected at 350 mu m. The sample includes galaxies discovered in the deepest blank-field survey at 350 mu m (in the Bootes Deep Field) and also later serendipitous detections in the Lockman Hole. In determining multiwavelength identifications, the 350 mu m position and map resolution of the second generation Submillimeter High Angular Resolution Camera are critical, especially in the cases where multiple radio sources exist and the 24 mu m counterparts are unresolved. Spectral energy distribution templates are fitted to identified counterparts, and the sample is found to comprise IR-luminous galaxies at 1 < z < 3 predominantly powered by star formation. The first spectrum of a 350 mu m selected galaxy provides an additional confirmation, showing prominent dust grain features typically associated with star-forming galaxies. Compared to submillimeter galaxies selected at 850 and 1100 mu m, galaxies selected at 350 mu m have a similar range of far-infrared color temperatures. However, no 350 mu m selected sources are reliably detected at 850 or 1100 mu m. Galaxies in our sample with redshifts 1 < z < 2 show a tight correlation between the far-and mid-infrared flux densities, but galaxies at higher redshifts show a large dispersion in their mid-to far-infrared colors. This implies a limit to which the mid-IR emission traces the far-IR emission in star-forming galaxies. The 350 mu m flux densities (15 < S(350) < 40 mJy) place these objects near the Herschel/SPIRE 350 mu m confusion threshold, with the lower limit on the star formation rate density suggesting the bulk of the 350 mu m contribution will come from less luminous infrared sources and normal galaxies. Therefore, the nature of the dominant source of the 350 mu m background-star-forming galaxies in the epoch of peak star formation in the universe-could be more effectively probed using ground-based instruments with their angular resolution and sensitivity offering significant advantages over space-based imaging.
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    Spitzer imaging of Herschel-atlas gravitationally lensed submillimeter sources.
    (2011) Hopwood, R.; Kim, Sam; Wardlow, Julie L.; Cooray, Asantha; Khostovan, A. A.; Negrello, Mattia; Cunha, E. da; Burgarella, D.; Aretxaga, I.; Auld, R.; Baes, M.
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    The Detection of a Population of Submillimeter-Bright, Strongly Lensed Galaxies.
    (2010) Negrello, Mattia; Kim, Sam; Hopwood, R.; Zotti, G. de; Cooray, Asantha; Verma, A.; Bock, J.; Frayer, D. T.; Gurwell, M. A.; Omont, A.; Neri, R.