High‐Resolution Simulations of Non‐Gaussian Cosmic Microwave Background Maps in Spherical Coordinates

We describe a new numerical algorithm for obtaining high-resolution simulated maps of the cosmic microwave background (CMB) for a broad class of non-Gaussian models. The kind of non-Gaussianity we account for is based on the simple idea that the primordial gravitational potential is obtained by a nonlinear but local mapping from an underlying Gaussian random field, as results from a variety of inflationary models. Our technique, which is based on a direct realization of the potential in spherical coordinates and fully accounts for the radiation transfer function, allows us to simulate non-Gaussian CMB maps down to the Planck resolution ( l max ~ 3000) with reasonable memory storage and computational time.