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A Lyman Break Galaxy Candidate at z ~ 9

Henry, Alaina L. and Malkan, Matthew A. and Colbert, James W. and Siana, Brian and Teplitz, Harry I. and McCarthy, Patrick (2008) A Lyman Break Galaxy Candidate at z ~ 9. Astrophysical Journal Letters, 680 (1). L97-L100. ISSN 2041-8205. doi:10.1086/589944.

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We report the discovery of a z ~ 9 Lyman break galaxy candidate, selected from the NICMOS Parallel Imaging Survey as a J-dropout with J110 − H160 = 1.7. Spitzer/IRAC photometry reveals that the galaxy has a blue H160 − 3.6 μm color and a spectral break between 3.6 and 4.5 μm. We interpret this break as the Balmer break and derive a best-fit photometric redshift of z ~ 9. We use Monte Carlo simulations to test the significance of this photometric redshift, and we show that there is a 96% probability of z ≥ 7. We estimate that the lower limit to the comoving number density of such galaxies at z ~ 9 is phi > 3.8 × 10^−6 Mpc^−3. If the high redshift of this galaxy is confirmed, this will indicate that the luminous end of the rest-frame UV luminosity function has not evolved substantially from z ~ 9 to z ~ 3. Still, some small degeneracy remains between this z ~ 9 model and models at z ~ 2–3; deep optical imaging (reaching IAB ~ 29) can rule out the lower z models.

Item Type:Article
Related URLs:
URLURL TypeDescription
Henry, Alaina L.0000-0002-6586-4446
Malkan, Matthew A.0000-0001-6919-1237
Siana, Brian0000-0002-4935-9511
Teplitz, Harry I.0000-0002-7064-5424
Additional Information:© 2008. The American Astronomical Society. Received 2008 February 6; accepted 2008 May 8; published 2008 June 20. Print publication: Issue 2 (2008 June 20). This research was supported by NASA through Hubble Space Telescope Guest Observer grant 10899. We thank the Spitzer director, T. Soifer, for the award of the DDT. Ned Wright's Javascript Cosmology Calculator was used in preparation of this Letter. We are grateful to C. Papovich for helpful comments that improved this manuscript. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory (JPL), California Institute of Technology, under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL/Caltech. This work is also based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with proposals 9484, 9865, 10226, and 10899.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Space Telescope Science InstituteUNSPECIFIED
NASANAS 5-26555
Subject Keywords:galaxies: evolution; galaxies: formation; galaxies: high-redshift
Issue or Number:1
Record Number:CaltechAUTHORS:HENapjl08
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:13040
Deposited By: Archive Administrator
Deposited On:16 Jan 2009 08:04
Last Modified:08 Nov 2021 22:35

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