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The CFHT Large Area U-band Deep Survey


In a few words

The CFHT Large Area U-band Deep Survey (CLAUDS) is a Canada-France-China collaboration to obtain deep CFHT U-band imaging to an unprecedented combination of area and depth (~20 sq deg to U~27AB at SNR=5).  CLAUDS overlaps with the Subaru Hyper Suprime-Cam (HSC) survey Deep/UltraDeep fields and greatly enhances the Subaru grizy dataset: it allows the selection of star-forming galaxies at z~2-3, measurement of star formation rates at z<1, and dramatically improves photometric redshift performance of the combined surveys. The CLAUDS data (equivalent to 68 dedicated CFHT dark-time nights plus archival data) are all in hand, and merged with the HSC dataset from our Subaru partners. Together, these catalogs are ideal for a large range of scientific applications from detailed galaxy evolutions studies over 0<z<1, to assembling large samples of galaxies, quasars and protoclusters at z~2-3. We are working on many of these topics, and have published over 20 papers on them already, but we have barely begun to scratch the surface and there is so much science to do with this incredibly rich dataset!

Credit image : By Gordon W Myers - Own work, CC BY-SA 4.0,

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