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Search for Galaxies at z>4 from a Deep Multicolor Survey

E. Giallongo·S. Charlot·S. Cristiani·S. D'Odorico·A. Fontana
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Abstract

We present deep BVrI multicolor photometry in the field of the quasar BR1202-07 (z_{em}=4.694) aimed at selecting field galaxies at z>4. We compare the observed colors of the galaxies in the field with those predicted by spectral synthesis models including UV absorption by the intergalactic medium and we define a robust multicolor selection of galaxies at z>4. We provide spectroscopic confirmation of the high redshift QSO-companion galaxy (z=4.702) selected by our method. The first estimate of the surface density of galaxies in the redshift interval 4<z<4.5 is obtained for the same field, corresponding to a comoving volume density of ~ 10^{-3}$ Mpc$^{-3}. This provides a lower limit to the average star formation rate of the order of 10^{-2} Mo/yr/Mpc^{-3} at z~ 4.25.

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E. Giallongo, S. Charlot, S. Cristiani, S. D'Odorico, A. Fontana. 1996-05-31. Search for Galaxies at z>4 from a Deep Multicolor Survey. https://arxiv.org/abs/astro-ph/9605196

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