Common-Resolution Convolution Kernels for Space- and Ground-Based Telescopes

Abstract

Multiwavelength study of extended astronomical objects requires combining images from instruments with differing point-spread functions (PSFs). We describe the construction of convolution kernels that allow one to generate (multiwavelength) images with a common PSF, thus preserving the colors of the astronomical sources. We generate convolution kernels for the cameras of Spitzer, Herschel Space Observatory, Galaxy Evolution Explorer (GALE), Wide-field Infrared Survey Explorer (WISE), ground-based optical telescopes (Moffat functions and sum of Gaussians), and Gaussian PSFs. Kernels for other telescopes including IRAS, AKARI, and Planck, are currently being constructed. These kernels allow the study of the spectral energy distribution (SED) of extended objects, preserving the characteristic SED in each pixel. The convolution kernels and the IDL packages used to construct and use them are made publicly available.