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arXiv · astro-ph/0405624

Deep mid-infrared observations of Lyman-break galaxies

P. Barmby·J. -S. Huang·G. G Fazio·J. A. Surace·R. G. Arendt·J. L. Hora·M. A. Pahre·K. L. Adelberger·P. Eisenhardt·D. K. Erb·M. Pettini·W. T. Reach·N. A. Reddy·A. E. Shapley·C. C. Steidel·D. Stern·Z. Wang·S. P. Willner
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Abstract

As part of the In-Orbit Checkout activities for the Spitzer Space Telescope, the IRAC team carried out a deep observation (average integration time ~8 hours) of a field surrounding the bright QSO HS 1700+6416. This field contains several hundred z~3 Lyman-break galaxy candidates, and we report here on their mid-infrared properties, including the IRAC detection rate, flux densities and colors, and the results of fitting population synthesis models to the optical, near-infrared, and IRAC magnitudes. The results of the model-fitting show that previous optical/near-infrared studies of LBGs were not missing large, hidden old stellar populations. The LBG candidates' properties are consistent with those of massive, star-forming galaxies at z~3. Other IRAC sources in the same field have similar properties, so IRAC selection may prove a promising method of finding additional high-redshift galaxies.

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P. Barmby, J. -S. Huang, G. G Fazio, J. A. Surace, R. G. Arendt, J. L. Hora, M. A. Pahre, K. L. Adelberger, P. Eisenhardt, D. K. Erb, M. Pettini, W. T. Reach, N. A. Reddy, A. E. Shapley, C. C. Steidel, D. Stern, Z. Wang, S. P. Willner. 2004-05-31. Deep mid-infrared observations of Lyman-break galaxies. https://doi.org/10.1086/422712

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