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The 2012 Hubble Ultra Deep Field (UDF12): Observational Overview

Koekemoer, Anton M. and Ellis, Richard S. and McLure, Ross J. and Dunlop, James S. and Robertson, Brant E. and Ono, Yoshiaki and Schenker, Matthew A. and Ouchi, Masami and Bowler, Rebecca A. A. 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 and Wild, V. and Targett, T. (2013) The 2012 Hubble Ultra Deep Field (UDF12): Observational Overview. Astrophysical Journal Supplement Series, 209 (1). Art. No. 3. ISSN 0067-0049. doi:10.1088/0067-0049/209/1/3.

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We present the 2012 Hubble Ultra Deep Field campaign (UDF12), a large 128 orbit Cycle 19 Hubble Space Telescope program aimed at extending previous Wide Field Camera 3 (WFC3)/IR observations of the UDF by quadrupling the exposure time in the F105W filter, imaging in an additional F140W filter, and extending the F160W exposure time by 50%, as well as adding an extremely deep parallel field with the Advanced Camera for Surveys (ACS) in the F814W filter with a total exposure time of 128 orbits. The principal scientific goal of this project is to determine whether galaxies reionized the universe; our observations are designed to provide a robust determination of the star formation density at z ≳ 8, improve measurements of the ultraviolet continuum slope at z ~ 7-8, facilitate the construction of new samples of z ~ 9-10 candidates, and enable the detection of sources up to z ~ 12. For this project we committed to combining these and other WFC3/IR imaging observations of the UDF area into a single homogeneous dataset to provide the deepest near-infrared observations of the sky. In this paper we present the observational overview of the project and describe the procedures used in reducing the data as well as the final products that were produced. We present the details of several special procedures that we implemented to correct calibration issues in the data for both the WFC3/IR observations of the main UDF field and our deep 128 orbit ACS/WFC F814W parallel field image, including treatment for persistence, correction for time-variable sky backgrounds, and astrometric alignment to an accuracy of a few milliarcseconds. We release the full, combined mosaics comprising a single, unified set of mosaics of the UDF, providing the deepest near-infrared blank-field view of the universe currently achievable, reaching magnitudes as deep as AB ~ 30 mag in the near-infrared, and yielding a legacy dataset on this field.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Koekemoer, Anton M.0000-0002-6610-2048
Ellis, Richard S.0000-0001-7782-7071
Robertson, Brant E.0000-0002-4271-0364
Ouchi, Masami0000-0002-1049-6658
Furlanetto, Steven R.0000-0002-0658-1243
Additional Information:© 2013 American Astronomical Society. Received 2012 December 6; accepted 2013 September 9; published 2013 October 11. We thank the referee for very useful comments that helped to improve this manuscript. We wish to thank the Hubble observing team as well as our Program Coordinator, Shelley Meyett, for help in scheduling and executing this program. Support for HST Program GO-12498 is provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5- 26555. J.S.D., R.A.A.B., T.A.T., and V.W. acknowledge the support of the European Research Council through the award of an Advanced Grant to J.S.D. In addition, J.S.D. and R.J.M. acknowledge the support of the Royal Society via a Wolfson Research Merit Award and a University Research Fellowship, respectively. A.B.R. and E.F.C.L. acknowledge the support of the UK Science and Technology Facilities Council. V.W. acknowledges the support of the European Research Council through the award of a Starting Grant. S.C. acknowledges the support of the European Commission through the Marie Curie Initial Training Network ELIXIR. Facility: HST (ACS, WFC3)
Funding AgencyGrant Number
NASANAS5- 26555
European Research Council (ERC)UNSPECIFIED
Science and Technology Facilities Council (STFC)UNSPECIFIED
Marie Curie FellowshipUNSPECIFIED
Subject Keywords: cosmology: observations; galaxies: high-redshift
Issue or Number:1
Record Number:CaltechAUTHORS:20131205-094419136
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Official Citation:The 2012 Hubble Ultra Deep Field (UDF12): Observational Overview Anton M. Koekemoer et al. 2013 ApJS 209 3
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:42853
Deposited By: Ruth Sustaita
Deposited On:05 Dec 2013 18:10
Last Modified:10 Nov 2021 16:29

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