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		| Paper: | 
		The Star Formation Density at z∼7 | 
	 
	
		| Volume: | 
		380, At the Edge of the Universe: Latest Results from the Deepest Astronomical Surveys | 
	 
	
		| Page: | 
		87 | 
	 
	
		| Authors: | 
		Mannucci, F. | 
	 
	
	
		| Abstract: | 
		Near-infrared VLT data of the GOODS-South area were used to look for galaxies at z~7 down to a limiting magnitude of (J+Ks)AB=25.5. No high-redshift candidates were detected, and this provides clear evidence for a strong evolution of the luminosity function between z=6 and z=7, i.e. over a time interval of only ~170 Myr. Our constraints provide evidence of a significant decline in the total star formation rate at z=7, which must be less than 40% of that at z=3 and 40-80% of that at z=6. The resulting upper limit to the ionizing flux at z=7 is only marginally consistent with what is required to completely ionize the Universe. | 
	 
	
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