A Caltech Library Service

The Abundance of Star-forming Galaxies in the Redshift Range 8.5-12: New Results from the 2012 Hubble Ultra Deep Field Campaign

Ellis, Richard S. and McLure, Ross J. and Dunlop, James S. and Robertson, Brant E. and Ono, Yoshiaki and Schenker, Matthew A. and Koekemoer, Anton M. and Bowler, Rebecca A. A. and Ouchi, Masami and Rogers, Alexander B. and Curtis-Lake, Emma and Schneider, Evan and Charlot, Stéphane and Stark, Daniel P. and Furlanetto, Steven R. and Cirasuolo, Michele (2013) The Abundance of Star-forming Galaxies in the Redshift Range 8.5-12: New Results from the 2012 Hubble Ultra Deep Field Campaign. Astrophysical Journal Letters, 763 (1). Art. No. L7. ISSN 2041-8205. doi:10.1088/2041-8205/763/1/L7.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present the results of the deepest search to date for star-forming galaxies beyond a redshift z ≃ 8.5 utilizing a new sequence of near-infrared Wide-Field Camera 3 (WFC3/IR) images of the Hubble Ultra Deep Field (UDF). This "UDF12" campaign completed in 2012 September doubles the earlier exposures with WFC3/IR in this field and quadruples the exposure in the key F105W filter used to locate such distant galaxies. Combined with additional imaging in the F140W filter, the fidelity of high-redshift candidates is greatly improved. Using spectral energy distribution fitting techniques on objects selected from a deep multi-band near-infrared stack, we find seven promising z > 8.5 candidates. As none of the previously claimed UDF candidates with 8.5 < z < 10 are confirmed by our deeper multi-band imaging, our campaign has transformed the measured abundance of galaxies in this redshift range. Although we recover the candidate UDFj-39546284 (previously proposed at z = 10.3), it is undetected in the newly added F140W image, implying that it lies at z = 11.9 or is an intense emission line galaxy at z ≃ 2.4. Although no physically plausible model can explain the required line intensity given the lack of Lyα or broadband UV signal, without an infrared spectrum we cannot rule out an exotic interloper. Regardless, our robust z ≃ 8.5-10 sample demonstrates a luminosity density that continues the smooth decline observed over 6 < z < 8. Such continuity has important implications for models of cosmic reionization and future searches for z >10 galaxies with James Webb Space Telescope.

Item Type:Article
Related URLs:
URLURL TypeDescription
Ellis, Richard S.0000-0001-7782-7071
Robertson, Brant E.0000-0002-4271-0364
Koekemoer, Anton M.0000-0002-6610-2048
Ouchi, Masami0000-0002-1049-6658
Furlanetto, Steven R.0000-0002-0658-1243
Additional Information:© 2013 American Astronomical Society. Received 2012 November 6; accepted 2012 December 5; published 2012 December 27. The U.S. authors acknowledge financial support from the Space Telescope Science Institute under award HST-GO- 12498.01-A. J.S.D. acknowledges support of the European Research Council and the Royal Society. R.J.M. acknowledges funding from the Leverhulme Trust. We thank Kimihiko Nakajima for assistance with the Keck spectroscopy. This work is based on data from the Hubble Space Telescope operated by NASA through the Space Telescope Science Institute via the association of Universities for Research in Astronomy, Inc. under contract NAS5-26555.
Funding AgencyGrant Number
European Research Council (ERC)UNSPECIFIED
Leverhulme TrustUNSPECIFIED
Subject Keywords:dark ages, reionization, first stars; galaxies: evolution; galaxies: formation; galaxies: stellar content
Issue or Number:1
Record Number:CaltechAUTHORS:20130215-113614416
Persistent URL:
Official Citation:The Abundance of Star-forming Galaxies in the Redshift Range 8.5-12: New Results from the 2012 Hubble Ultra Deep Field Campaign Richard S. Ellis et al. 2013 ApJ 763 L7
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:36960
Deposited On:15 Feb 2013 21:05
Last Modified:09 Nov 2021 23:25

Repository Staff Only: item control page