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arXiv · 0908.0343

Deep Keck u-band imaging of the Hubble Ultra Deep Field: A catalog of z~3 Lyman Break Galaxies

Marc Rafelski·Arthur M. Wolfe·Jeff Cooke·Hsiao-Wen Chen·Taft E. Armandroff·Gregory D. Wirth
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Abstract

We present a sample of 407 z~3 Lyman break galaxies (LBGs) to a limiting isophotal u-band magnitude of 27.6 mag in the Hubble Ultra Deep Field (UDF). The LBGs are selected using a combination of photometric redshifts and the u-band drop-out technique enabled by the introduction of an extremely deep u-band image obtained with the Keck I telescope and the blue channel of the LRIS spectrometer. The Keck u-band image, totaling 9 hours of integration time, has a one sigma depth of 30.7 mag arcsec^-2, making it one of the most sensitive u-band images ever obtained. The u-band image also substantially improves the accuracy of photometric redshift measurements of ~50% of the z~3 Lyman break galaxies, significantly reducing the traditional degeneracy of colors between z~3 and z~0.2 galaxies. This sample provides the most sensitive, high-resolution multi-filter imaging of reliably identified z~3 LBGs for morphological studies of galaxy formation and evolution and the star formation efficiency of gas at high redshift.

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Marc Rafelski, Arthur M. Wolfe, Jeff Cooke, Hsiao-Wen Chen, Taft E. Armandroff, Gregory D. Wirth. 2009-08-03. Deep Keck u-band imaging of the Hubble Ultra Deep Field: A catalog of z~3 Lyman Break Galaxies. https://doi.org/10.1088/0004-637x/703/2/2033

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