Advanced search
1 file | 468.22 KB

Herschel-ATLAS: toward a sample of ~1000 strongly lensed galaxies

Author
Organization
Abstract
While the selection of strongly lensed galaxies (SLGs) with 500 mu m flux density S-500 > 100 mJy has proven to be rather straightforward, for many applications it is important to analyze samples larger than the ones obtained when confining ourselves to such a bright limit. Moreover, only by probing to fainter flux densities is it possible to exploit strong lensing to investigate the bulk of the high-z star-forming galaxy population. We describe HALOS (the Herschel-ATLAS Lensed Objects Selection), a method for efficiently selecting fainter candidate SLGs, reaching a surface density of similar or equal to 1.5-2 deg(-2), i.e., a factor of about 4-6 higher than that at the 100 mJy flux limit. HALOS will allow the selection of up to similar to 1000 candidate SLGs (with amplifications mu greater than or similar to 2) over the full H-ATLAS survey area. Applying HALOS to the H-ATLAS Science Demonstration Phase field (similar or equal to 14.4deg(2)) we find 31 candidate SLGs, whose candidate lenses are identified in the VIKING near-infrared catalog. Using the available information on candidate sources and candidate lenses we tentatively estimate a similar or equal to 72% purity of the sample. As expected, the purity decreases with decreasing flux density of the sources and with increasing angular separation between candidate sources and lenses. The redshift distribution of the candidate lensed sources is close to that reported for most previous surveys for lensed galaxies, while that of candidate lenses extends to redshifts substantially higher than found in the other surveys. The counts of candidate SLGs are also in good agreement with model predictions. Even though a key ingredient of the method is the deep near-infrared VIKING photometry, we show that H-ATLAS data alone allow the selection of a similarly deep sample of candidate SLGs with an efficiency close to 50%; a slightly lower surface density (similar or equal to 1.45 deg(-2)) can be reached with a similar to 70% efficiency.
Keywords
galaxies: high-redshift, gravitational lensing: strong, submillimeter: galaxies, STAR-FORMATION, SIZE EVOLUTION, ELLIPTIC GALAXIES, VELOCITY DISPERSION, CANDIDATE SELECTION, EXTRAGALACTIC SOURCES, HIGH-REDSHIFT, SKY SURVEY, SCIENCE DEMONSTRATION PHASE, SUBMILLIMETER GALAXY

Downloads

  • (...).pdf
    • full text
    • |
    • UGent only
    • |
    • PDF
    • |
    • 468.22 KB

Citation

Please use this url to cite or link to this publication:

Chicago
Gonzalez-Nuevo, J, A Lapi, S Fleuren, S Bressan, L Danese, G De Zotti, M Negrello, et al. 2012. “Herschel-ATLAS: Toward a Sample of ~1000 Strongly Lensed Galaxies.” Astrophysical Journal 749 (1).
APA
Gonzalez-Nuevo, J., Lapi, A., Fleuren, S., Bressan, S., Danese, L., De Zotti, G., Negrello, M., et al. (2012). Herschel-ATLAS: toward a sample of ~1000 strongly lensed galaxies. ASTROPHYSICAL JOURNAL, 749(1).
Vancouver
1.
Gonzalez-Nuevo J, Lapi A, Fleuren S, Bressan S, Danese L, De Zotti G, et al. Herschel-ATLAS: toward a sample of ~1000 strongly lensed galaxies. ASTROPHYSICAL JOURNAL. 2012;749(1).
MLA
Gonzalez-Nuevo, J, A Lapi, S Fleuren, et al. “Herschel-ATLAS: Toward a Sample of ~1000 Strongly Lensed Galaxies.” ASTROPHYSICAL JOURNAL 749.1 (2012): n. pag. Print.
@article{2113336,
  abstract     = {While the selection of strongly lensed galaxies (SLGs) with 500 mu m flux density S-500 {\textrangle} 100 mJy has proven to be rather straightforward, for many applications it is important to analyze samples larger than the ones obtained when confining ourselves to such a bright limit. Moreover, only by probing to fainter flux densities is it possible to exploit strong lensing to investigate the bulk of the high-z star-forming galaxy population. We describe HALOS (the Herschel-ATLAS Lensed Objects Selection), a method for efficiently selecting fainter candidate SLGs, reaching a surface density of similar or equal to 1.5-2 deg(-2), i.e., a factor of about 4-6 higher than that at the 100 mJy flux limit. HALOS will allow the selection of up to similar to 1000 candidate SLGs (with amplifications mu greater than or similar to 2) over the full H-ATLAS survey area. Applying HALOS to the H-ATLAS Science Demonstration Phase field (similar or equal to 14.4deg(2)) we find 31 candidate SLGs, whose candidate lenses are identified in the VIKING near-infrared catalog. Using the available information on candidate sources and candidate lenses we tentatively estimate a similar or equal to 72\% purity of the sample. As expected, the purity decreases with decreasing flux density of the sources and with increasing angular separation between candidate sources and lenses. The redshift distribution of the candidate lensed sources is close to that reported for most previous surveys for lensed galaxies, while that of candidate lenses extends to redshifts substantially higher than found in the other surveys. The counts of candidate SLGs are also in good agreement with model predictions. Even though a key ingredient of the method is the deep near-infrared VIKING photometry, we show that H-ATLAS data alone allow the selection of a similarly deep sample of candidate SLGs with an efficiency close to 50\%; a slightly lower surface density (similar or equal to 1.45 deg(-2)) can be reached with a similar to 70\% efficiency.},
  articleno    = {65},
  author       = {Gonzalez-Nuevo, J and Lapi, A and Fleuren, S and Bressan, S and Danese, L and De Zotti, G and Negrello, M and Cai, ZY and Fan, L and Sutherland, W and Baes, Maarten and Baker, AJ and Clements, L and Cooray, A and Dannerbauer, H and Dunne, L and Dye, S and Eales, S and Frayer, DT and Harris, AI and Ivison, R and Jarvis, MJ and Michallowski, MJ and Lopez-Caniego, M and Rodighiero, G and Rowlands, K and Serjeant, S and Scott, D and van der Werf, P and Auld, R and Buttiglione, S and Cava, A and Dariush, A and Fritz, Jacopo and Hopwood, R and Ibar, E and Maddox, S and Pascale, E and Pohlen, M and Rigby, E and Smith, D and Temi, P},
  issn         = {0004-637X},
  journal      = {ASTROPHYSICAL JOURNAL},
  language     = {eng},
  number       = {1},
  pages        = {12},
  title        = {Herschel-ATLAS: toward a sample of {\texttildelow}1000 strongly lensed galaxies},
  url          = {http://dx.doi.org/10.1088/0004-637X/749/1/65},
  volume       = {749},
  year         = {2012},
}

Altmetric
View in Altmetric
Web of Science
Times cited: