| タイトル | Extremely Red Objects in the Lockman Hole |
| 著者（英） | Alonso-Herrero, A.; Rieke, G. H.; Dole, H.; Egami, E.; Gordon, K. D.; Miyazaki, S.; Perez-Gonzalez, P. G.; Rigby, J. R.; Surace, J.; Bai, L; Ivison, R. J.; Morrison, J. E.; Engelbracht, C. W.; Huang, J. -S.; Rigopoulou, D.; Fazio, G. G.; Wilson, G.; Hines, D. C.; LeFloch, E.; Barmby, P.; Rieke, M. J.; Misselt, K. A.; Papovich, C.; Frayer, D. |
| 著者所属（英） | Jet Propulsion Lab., California Inst. of Tech. |
| 発行日 | 2004-09-01 |
| 言語 | eng |
| 内容記述 | We investigate extremely red objects (EROs) using near- and mid-infrared observations in five passbands (3.6 to 24 microns) obtained from the Spitzer Space Telescope, and deep ground-based R and K imaging. The great sensitivity of the Infrared Array Camera (IRAC) camera allows us to detect 64 EROs (a surface density of 2.90 +/- 0.36 arcmin(exp -2); [3.6](sub AB) is less than 23.7) in only 12 minutes of IRAC exposure time, by means of an R - [3.6] color cut (analogous to the traditional red R - K cut). A pure infrared K - [3.6] red cut detects a somewhat different population and may be more effective at selecting z greater than 1.3 EROs. We find approximately 17% of all galaxies detected by IRAC at 3.6 or 4.5 microns to be EROs. These percentages rise to about 40% at 5.8 microns, and about 60% at 8.0 microns. We utilize the spectral bump at 1.6 microns to divide the EROs into broad redshift slices using only near-infrared colors (2.2/3.6/4.5 microns). We conclude that two-thirds of all EROs lie at redshift z greater than 1.3. Detections at 24 microns imply that at least 11% of 0.6 less than z and less than 1.3 EROs and at least 22% of z greater than 1.3 EROs are dusty star-forming galaxies. |
| NASA分類 | Astrophysics |
| 権利 | Copyright |
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