Browsing by Author "Chapman, S. C."

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    HerMES: CANDIDATE HIGH-REDSHIFT GALAXIES DISCOVERED WITH HERSCHEL/SPIRE
    (2014) Dowell, C. Darren; Conley, A.; Glenn, J.; Arumugam, V.; Asboth, V.; Aussel, H.; Bertoldi, F.; Bethermin, M.; Bock, J.; Boselli, A.; Bridge, C.; Buat, V.; Burgarella, D.; Cabrera-Lavers, A.; Casey, C. M.; Chapman, S. C.; Clements, D. L.; Conversi, L.; Cooray, A.; Dannerbauer, H.; De Bernardis, F.; Ellsworth-Bowers, T. P.; Farrah, D.; Franceschini, A.; Griffin, M.; Gurwell, M. A.; Halpern, M.; Hatziminaoglou, E.; Heinis, S.; Ibar, E.; Ivison, R. J.; Laporte, N.; Marchetti, L.; Martinez-Navajas, P.; Marsden, G.; Morrison, G. E.; Nguyen, H. T.; O'Halloran, B.; Oliver, S. J.; Omont, A.; Page, M. J.; Papageorgiou, A.; Pearson, C. P.; Petitpas, G.; Perez-Fournon, I.; Pohlen, M.; Riechers, D.; Rigopoulou, D.; Roseboom, I. G.; Rowan-Robinson, M.; Sayers, J.; Schulz, B.; Scott, Douglas; Seymour, N.; Shupe, D. L.; Smith, A. J.; Streblyanska, A.; Symeonidis, M.; Vaccari, M.; Valtchanov, I.; Vieira, J. D.; Viero, M.; Wang, L.; Wardlow, J.; Xu, C. K.; Zemcov, M.
    We present a method for selecting z > 4 dusty, star-forming galaxies (DSFGs) using Herschel/Spectral and Photometric Imaging Receiver 250/350/500 mu m flux densities to search for red sources. We apply this method to 21 deg(2) of data from the HerMES survey to produce a catalog of 38 high-z candidates. Follow-up of the first five of these sources confirms that this method is efficient at selecting high-z DSFGs, with 4/5 at z = 4.3-6.3 (and the remaining source at z = 3.4), and that they are some of the most luminous dusty sources known. Comparison with previous DSFG samples, mostly selected at longer wavelengths (e. g., 850 mu m) and in single-band surveys, shows that our method is much more efficient at selecting high-z DSFGs, in the sense that a much larger fraction are at z > 3. Correcting for the selection completeness and purity, we find that the number of bright (S-500 (mu m) >= 30 mJy), red Herschel sources is 3.3 +/- 0.8 deg(-2). This is much higher than the number predicted by current models, suggesting that the DSFG population extends to higher redshifts than previously believed. If the shape of the luminosity function for high-z DSFGs is similar to that at z similar to 2, rest-frame UV based studies may be missing a significant component of the star formation density at z = 4-6, even after correction for extinction.
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    SPT 0538-50: PHYSICAL CONDITIONS IN THE INTERSTELLAR MEDIUM OF A STRONGLY LENSED DUSTY STAR-FORMING GALAXY AT z=2.8
    (2013) Bothwell, M. S.; Aguirre, J. E.; Chapman, S. C.; Marrone, D. P.; Vieira, J. D.; Ashby, M. L. N.; Aravena, M.; Benson, B. A.; Bock, J. J.; Bradford, C. M.; Brodwin, M.; Carlstrom, J. E.; Crawford, T. M.; De Breuck, C.; Downes, T. P.; Fassnacht, C. D.; Gonzalez, A. H.; Greve, T. R.; Gullberg, B.; Hezaveh, Y.; Holder, G. P.; Holzapfel, W. L.; Ibar, E.; Ivison, R.; Kamenetzky, J.; Keisler, R.; Lupu, R. E.; Ma, J.; Malkan, M.; McIntyre, V.; Murphy, E. J.; Nguyen, H. T.; Reichardt, C. L.; Rosenman, M.; Spilker, J. S.; Stalder, B.; Stark, A. A.; Strandet, M.; Vernet, J.; Weiss, A.; Welikala, N.
    We present observations of SPT-S J053816-5030.8, a gravitationally lensed dusty star-forming galaxy (DSFG) at z = 2.7817 that was first discovered at millimeter wavelengths by the South Pole Telescope. SPT 0538-50 is typical of the brightest sources found by wide-field millimeter-wavelength surveys, being lensed by an intervening galaxy at moderate redshift (in this instance, at z = 0.441). We present a wide array of multi-wavelength spectroscopic and photometric data on SPT 0538-50, including data from ALMA, Herschel PACS and SPIRE, Hubble, Spitzer, the Very Large Telescope, ATCA, APEX, and the Submillimeter Array. We use high-resolution imaging from the Hubble Space Telescope to de-blend SPT 0538-50, separating DSFG emission from that of the foreground lens. Combined with a source model derived from ALMA imaging (which suggests a magnification factor of 21+/-4), we derive the intrinsic properties of SPT 0538-50, including the stellar mass, far-IR luminosity, star formation rate, molecular gas mass, and-using molecular line fluxes-the excitation conditions within the interstellar medium. The derived physical properties argue that we arewitnessing compact, merger-driven star formation in SPT 0538-50 similar to local starburst galaxies and unlike that seen in some other DSFGs at this epoch.
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    Sub-kiloparsec imaging of cool molecular gas in two strongly lensed dusty
    (2015) Spilker, J. S.; Aravena, M.; Marrone, D. P.; Bethermin, M.; Bothwell, M. S.; Carlstrom, J. E.; Chapman, S. C.; Collier, J. D.; De Breuck, C.; González López, Jorge