MID-INFRARED SPECTROSCOPY OF CANDIDATE ACTIVE GALACTIC NUCLEI-DOMINATED SUBMILLIMETER GALAXIES
MID-INFRARED SPECTROSCOPY OF CANDIDATE ACTIVE GALACTIC NUCLEI-DOMINATED SUBMILLIMETER GALAXIES
复制标题
候选活动星系核主导的亚毫米星系的中红外光谱
DOI:
10.1088/0004-637x/713/1/503
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发表时间:
2010
期刊:
影响因子:
--
通讯作者:
Coppin K
中科院分区:
文献类型:
--
作者:
Coppin K
Spitzer spectroscopy has revealed that≃ 80% of submm galaxies (SMGs) are starburst (SB)-dominated in the mid-infrared. Here we focus on the remaining≃ 20% that show signs of harboring powerful active galactic nuclei (AGNs). We have obtained Spitzer-InfraRed Spectrograph spectroscopy of a sample of eight SMGs that are candidates for harboring powerful AGNs on the basis of IRAC color selection (S 8 μm/S 4.5 μm> 2, ie, likely power-law mid-infrared spectral energy distributions). SMGs with an AGN dominating (≳ 50%) their mid-infrared emission could represent the" missing link" sources in an evolutionary sequence involving a major merger. First of all, we detect polycyclic aromatic hydrocarbon (PAH) features in all of the SMGs, indicating redshifts from 2.5 to 3.4, demonstrating the power of the mid-infrared to determine redshifts for these optically faint dusty galaxies. Second, we see signs of both star formation (from the PAH features) and AGN activity (from continuum emission) in our sample: 62% of the sample are AGN-dominated in the mid-infrared with a median AGN content of 56%, compared with< 30% on average for typical SMGs, revealing that our IRAC color selection has successfully singled out sources with proportionately more AGN emission than typical SB-dominated SMGs. However, we find that only about 10% of these AGNs dominate the bolometric emission of the SMG when the results are extrapolated to longer infrared wavelengths, implying that AGNs are not a significant power source to the SMG population overall, even when there is evidence in the mid-infrared for substantial AGN activity. When existing samples of mid-infrared AGN-dominated SMGs are considered, we find that S 8 μm/S 4.5 μm> 1.65 works well at selecting mid-infrared energetically dominant AGNs in SMGs, implying a duty cycle of∼ 15% if all SMGs go through a subsequent mid-infrared AGN-dominated phase in the proposed evolutionary sequence.
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DOI:
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发表时间:
2000
期刊:
影响因子:
--
作者:
D. Lutz;E. Sturm;R. Genzel;A. Moorwood;T. Alexander;H. Netzer;A. Sternberg
通讯作者:
A. Sternberg
DOI:
10.1111/j.1365-2966.2005.09639.x
发表时间:
2004
影响因子:
4.8
作者:
R. Ivison;R. Ivison;I. Smail;J. Dunlop;T. Greve;A. Swinbank;J. Stevens;J. Stevens;A. Mortier;S. Serjeant;T. Targett;F. Bertoldi;A. Blain;Stephen Chapman
通讯作者:
Stephen Chapman
DOI:
10.1086/320543
发表时间:
2001
期刊:
The Astrophysical Journal
影响因子:
--
作者:
Q. D. Tran;D. Lutz;R. Genzel;D. Rigopoulou;H. Spoon;E. Sturm;M. Gerin;D. Hines;A. Moorwood;D. Sanders;N. Scoville;Y. Taniguchi;M. W. M. E. Ens;Paris Steward Observatory University of Hawaii Californi University
通讯作者:
Paris Steward Observatory University of Hawaii Californi University
DOI:
--
发表时间:
2006
期刊:
影响因子:
--
作者:
M. Ashby;S. Dye;J.;S. Eales;S. Willner;T. Webb;P. Barmby;D. Rigopoulou;E. Egami;H. McCracken;S. Lilly;S. Miyazaki;M. Brodwin;M. Blaylock;J. Cadien;G. Fazio
通讯作者:
G. Fazio
DOI:
--
发表时间:
2001
期刊:
影响因子:
--
作者:
E. Archibald;J. Dunlop;R. Jimenez;A. Friaça;R. McLure;D. Hughes
通讯作者:
D. Hughes