Large Area Lyman Alpha survey : finding young galaxies at z = 4 . 5
نویسندگان
چکیده
Strong Lyman-α emission is a signpost of young stars and the absence of dust and thus indicates young galaxies. To find such a population of young galaxies at z=4.5 we started the Large Area Lyman Alpha survey (LALA). This survey achieves an unprecedented combination of volume and sensitivity by using narrow-band filters on a large format (36 ×36) camera on the 4 meter telescope at KPNO. The volume density and starformation contribution of the Lyman-α emitters at z=4.5 is comparable to that of Lyman break galaxies. With many candidates and a few spectroscopic confirmations in hand we discuss what the properties of Ly-α emitters imply for galaxy and star formation in the early universe.
منابع مشابه
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