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Searching for the Sources Responsible for Cosmic Reionization: Probing 7 < z < 10 and Beyond

Daniel P. Stark·Richard S. Ellis
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Abstract

(Abridged) We review recent observations that suggest the star formation rate density is declining over 3$<z<$7 and illustrate the challenges that this poses in explaining the assembled stellar mass in z$\sim$6 galaxies deduced from Spitzer data. A plausible conclusion is a vigorous period of earlier star formation. Prior to JWST and TMT, strong lensing offers a unique probe of the extent of this earlier activity. We discuss the first results of a blind spectroscopic survey of lensing clusters for 8.5$<z<$10 Ly$α$ emitters using NIRSPEC which is achieving a limiting star formation rate of 0.1 $M_{\odot}$ yr$^{-1}$. A companion HST/IRAC survey is targeting lensed $z$ and $J$-band dropouts and probes a $\simeq$1 arcmin$^2$ region 1 magnitude deeper than the UDF/NICMOS observations. Both surveys will constrain the contribution of early, low luminosity, sources to cosmic reionization.

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Daniel P. Stark, Richard S. Ellis. 2005-08-04. Searching for the Sources Responsible for Cosmic Reionization: Probing 7 < z < 10 and Beyond. https://doi.org/10.1016/j.newar.2005.11.012

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