MegaCam pipeline at CFHT : present and immediate future
Jean-Charles Cuillandre (CFHT) , Nicolas Regnault (IN2P3), Pierre Astier (IN2P3), Eugene Magnier (IfA), Chris Pritchet (UVic), Mark Sullivan (Univ. of Toronto), Stephane Arnouts (CFHT), Kyan Schahmaneche (IN2P3)

Abstract: Over the past four years, since the first light of the instrument, the MegaCam pipeline at CFHT (Elixir) has processed more than 85,000 images, approximately 50 Terabytes worth of data. The detrending recipes (pre-processing) have evolved over that period mostly on the photometric flatness correction, the most challenging aspect of the one square degree wide-field imaging capability offered by MegaPrime. The SNLS group has become deeply involved in solving limitations of the original Elixir pipeline, and we are now reaching a true photometric flatness of better than 0.5%25 across the entire field of view. Ancillary programs have emerged from the collaboration, such as the MegaPrime Absolute Photometric Calibration program which aims at branching together various photometric systems in order to derive a very precise absolute photometric calibration of the four CFHTLS Deep fields, with promises of terrific consequences on the photometric calibration of the entire MegaCam data set, CFHTLS and PIs programs alike.