A mid-infrared spectroscopic study of submillimeter galaxies: Luminous starbursts at high redshift

被引:125
作者
Valiante, E. [1 ]
Lutz, D.
Sturm, E.
Genzel, R.
Tacconi, L. J.
Lehnert, M. D.
Baker, A. J.
机构
[1] Max Planck Inst Extraterr Phys, D-85741 Garching, Germany
[2] Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA
关键词
galaxies : active; galaxies : distances and redshifts; galaxies : starburst; infrared : galaxies;
D O I
10.1086/513306
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present rest-frame mid-infrared spectroscopy of a sample of 13 submillimeter galaxies, obtained using the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope. The sample includes exclusively bright objects from blank fields and cluster lens-assisted surveys that have accurate interferometric positions. We find that the majority of spectra are well fitted by a starburst template or by the superposition of PAH emission features and a weak mid-infrared continuum, the latter a tracer of active galactic nuclei (AGNs; including Compton-thick ones). We obtain mid-infrared spectroscopic redshifts for all nine sources detected with IRS. For three of them the redshifts were previously unknown. The median value of the redshift distribution is z similar to 2.8 if we assume that the four IRS nondetections are at high redshift. The median for the IRS detections alone is z similar to 2.7. Placing the IRS nondetections at similar redshift would require rest-frame mid-IR obscuration larger than is seen in local ULIRGs. The rest-frame midinfrared spectra and mid- to far-infrared spectral energy distributions are consistent with those of local ultraluminous infrared galaxies but scaled up further in luminosity. The mid-infrared spectra support the scenario that submillimeter galaxies are sites of extreme star formation, rather than X-ray-obscured AGNs, and represent a critical phase in the formation of massive galaxies.
引用
收藏
页码:1060 / 1071
页数:12
相关论文
共 97 条
[1]   The X-ray spectral properties of scuba galaxies [J].
Alexander, DM ;
Bauer, FE ;
Chapman, SC ;
Smail, I ;
Blain, AW ;
Brandt, WN ;
Ivison, RJ .
ASTROPHYSICAL JOURNAL, 2005, 632 (02) :736-750
[2]   Rapid growth of black holes in massive star-forming galaxies [J].
Alexander, DM ;
Smail, I ;
Bauer, FE ;
Chapman, SC ;
Blain, AW ;
Brandt, WN ;
Ivison, RJ .
NATURE, 2005, 434 (7034) :738-740
[3]   The Chandra Deep Field North survey. XIV. X-ray detected obscured AGNs and starburst galaxies in the bright submillimeter source population [J].
Alexander, DM ;
Bauer, FE ;
Brandt, WN ;
Hornschemeier, AE ;
Vignali, C ;
Garmire, GP ;
Schneider, DP ;
Chartas, G ;
Gallagher, SC .
ASTRONOMICAL JOURNAL, 2003, 125 (02) :383-397
[4]  
[Anonymous], APJ
[5]   Breaking the 'redshift deadlock' -: II.: The redshift distribution for the submillimetre population of galaxies [J].
Aretxaga, I ;
Hughes, DH ;
Chapin, EL ;
Gaztañaga, E ;
Dunlop, JS ;
Ivison, RJ .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2003, 342 (03) :759-801
[6]   Redshift distribution of the faint submillimeter galaxy population [J].
Barger, AJ ;
Cowie, LL ;
Smail, I ;
Ivison, RJ ;
Blain, AW ;
Kneib, JP .
ASTRONOMICAL JOURNAL, 1999, 117 (06) :2656-2665
[7]   Submillimetre-wavelength detection of dusty star-forming galaxies at high redshift [J].
Barger, AJ ;
Cowie, LL ;
Sanders, DB ;
Fulton, E ;
Taniguchi, Y ;
Sato, Y ;
Kawara, K ;
Okuda, H .
NATURE, 1998, 394 (6690) :248-251
[8]   Can the faint submillimetre galaxies be explained in the cold dark matter model? [J].
Baugh, CM ;
Lacey, CG ;
Frenk, CS ;
Granato, GL ;
Silva, L ;
Bressan, A ;
Benson, AJ ;
Cole, S .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2005, 356 (03) :1191-1200
[9]   The evolution of galaxy mass in hierarchical models [J].
Baugh, CM ;
Benson, AJ ;
Cole, S ;
Frenk, CS ;
Lacey, C .
MASS OF GALAXIES AT LOW AND HIGH REDSHIFT, 2003, :91-96
[10]  
BAUTZ MW, 2000, APJ, V543, P119