BINGO: a code for the efficient computation of the scalar bi-spectrum

Abstract

We present a new and accurate Fortran code, the BI-spectra and\nNon-Gaussianity Operator (BINGO), for the efficient numerical computation of\nthe scalar bi-spectrum and the non-Gaussianity parameter f_{NL} in single field\ninflationary models involving the canonical scalar field. The code can\ncalculate all the different contributions to the bi-spectrum and the parameter\nf_{NL} for an arbitrary triangular configuration of the wavevectors. Focusing\nfirstly on the equilateral limit, we illustrate the accuracy of BINGO by\ncomparing the results from the code with the spectral dependence of the\nbi-spectrum expected in power law inflation. Then, considering an arbitrary\ntriangular configuration, we contrast the numerical results with the analytical\nexpression available in the slow roll limit, for, say, the case of the\nconventional quadratic potential. Considering a non-trivial scenario involving\ndeviations from slow roll, we compare the results from the code with the\nanalytical results that have recently been obtained in the case of the\nStarobinsky model in the equilateral limit. As an immediate application, we\nutilize BINGO to examine of the power of the non-Gaussianity parameter f_{NL}\nto discriminate between various inflationary models that admit departures from\nslow roll and lead to similar features in the scalar power spectrum. We close\nwith a summary and discussion on the implications of the results we obtain.\n