The Gamma Ray Imager/Polarimeter for Solar Flares (GRIPS): Monte-Carlo Simulations of the Instrument Performance.

The Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS) is a high-altitude balloon payload designed to study particle acceleration and transport in impulsive solar-flare. It consists of high purity germanium detectors (GeD) that measure the hard X-ray (> 20 keV) and Gamma-ray (up to or ≈ 10 MeV) photons' spectra and their polarization, and a single-grid, multi-pitch rotating modulator (MPRM) collimator that allows imaging at 12.5" resolution over the full Sun. In this work, we present a detailed Monte-Carlo simulations of the instrument performance.