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arXiv · 1002.4866

New Star Forming Galaxies at z\approx 7 from WFC3 Imaging

Stephen M. Wilkins·Andrew J. Bunker·Silvio Lorenzoni·Joseph Caruana
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Abstract

The addition of Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) has led to a dramatic increase in our ability to study the z>6 Universe. The increase in the near-infrared (NIR) sensitivity of WFC3 over previous instruments has enabled us to reach apparent magnitudes approaching 29 (AB). This allows us to probe the rest-frame ultraviolet (UV) continuum, redshifted into the NIR at $z>6$. Taking advantage of the large optical depths at this redshift, resulting in the Lyman-alpha break, we use a combination of WFC3 imaging and pre-existing Advanced Camera for Surveys (ACS) imaging to search for z approx 7 over 4 fields. Our analysis reveals 29 new z approx 7 star forming galaxy candidates in addition to 16 pre-existing candidates already discovered in these fields. The improved statistics from our doubling of the robust sample of z-drop candidates confirms the previously observed evolution of the bright end of the luminosity function.

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Stephen M. Wilkins, Andrew J. Bunker, Silvio Lorenzoni, Joseph Caruana. 2010-02-25. New Star Forming Galaxies at z\approx 7 from WFC3 Imaging. https://doi.org/10.1111/j.1365-2966.2010.17626.x

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