This paper describes the image stacks and catalogs of the CFHT Legacy Survey produced using the MegaPipe data pipeline at the Canadian Astronomy Data Centre .
The Legacy Survey is divided into to two parts : The Deep Survey consists of 4 fields each of 1 square degree , with magnitude limits ( 50 % completeness for point sources ) of u = 27.5 , g = 27.9 , r = 27.7 , i = 27.4 , and z = 26.2 , and contains 1.6 \times 10 ^ { 6 } sources .
The Wide Survey consists of 150 square degrees split over 4 fields , with magnitude limits of u = 26.0 , g = 26.5 , r = 25.9 , i = 25.7 , and z = 24.6 , and contains 3 \times 10 ^ { 7 } sources .
This paper describes the calibration , image stacking and catalog generation process .
The images and catalogs are available on the web through several interfaces : normal image and text file catalog downloads , a “ Google Sky ” interface , an image cutout service , and a catalog database query service .