Carnegie Mellon University
file.pdf (1.5 MB)

GALSIM: The modular galaxy image simulation toolkit

Download (1.5 MB)
journal contribution
posted on 2015-02-17, 00:00 authored by Barnaby Rowe, Mike Jarvis, Rachel MandelbaumRachel Mandelbaum, Gary M. Bernstein, James Bosch, Melanie SimetMelanie Simet, Joshua E. Meyers, Tomasz Kacprzak, Reiko Nakajima, Joe Zuntz, Hironao Miyatake, Jorg P. Dietrich, Robert Armstrong, Peter Melchior, Mandeep S. S. Gill

GalSim is a collaborative, open-source project aimed at providing an image simulation tool of enduring benefit to the astronomical community. It provides a software library for generating images of astronomical objects such as stars and galaxies in a variety of ways, efficiently handling image transformations and operations such as convolution and rendering at high precision. We describe the GalSim software and its capabilities, including necessary theoretical background. We demonstrate that the performance ofGalSim meets the stringent requirements of high precision image analysis applications such as weak gravitational lensing, for current datasets and for the Stage IV dark energy surveys of the Large Synoptic Survey Telescope, ESA’s Euclid mission, and NASA’sWFIRST-AFTA mission. The GalSim project repository is public and includes the full code history, all open and closed issues, installation instructions, documentation, and wiki pages (including a Frequently Asked Questions section). The GalSim repository can be found at


Publisher Statement

This is the author’s version of a work that was accepted for publication. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version is available at



Usage metrics



    Ref. manager