The Farmer: Improved model-based photometry for the next generation of galaxy surveys

While the increasing depth and area of galaxy surveys promise definitive high-redshift studies, ever more crowded sources challenge current photometric methodology. Pressed by the declining ratio of galaxies with spectroscopy to those without, we must pioneer methods to characterize these increasingly faint sources. Recent work by Lang and Hogg (2016) has provided another toolkit: The Tractor. By leveraging our understanding of galaxy morphologies, the Tractor is able to force galaxy models derived from high-resolution images onto less resolved ones, with superior deblending and robust photometric redshifts – advantageous for high-redshift studies. We present the Farmer, a comprehensive software interfacing with The Tractor to detect sources, efficiently determine the best model type for each source, and perform forced photometry in a scalable architecture. Built in part to exploit the future synergies of Spitzer/Euclid, the Farmer is here showcased with results from the next COSMOS catalog.