The Gamma Ray Imager/Polarimeter for Solar flares (GRIPS-2) is a high-altitude balloon payload designed to study particle acceleration and transport in impulsive solar-flares. It flew over Antarctica in January 2016 at a height of 130,000 ft, and the team is currently in the preparation phase for the second flight (scheduled for 2026). GRIPS-2 utilizes 16 double sided high-purity germanium strip detectors that measure photons’ spectra from 20keV to 10 MeV and their polarization, and a single-grid, multi-pitch rotating modulator (MPRM) collimator that allows imaging at 12.5 arcsec FWHM resolution over the full Sun. The energy and angular resolutions are suited to observe/image the 2.2 MeV neutron capture line and separate it from hard X-ray footpoints for almost all flares. GRIPS will address: (1) the spatial separation between electron and ions acceleration site, (2) the angular distribution of accelerated electrons, and (3) the spatial and temporal evolution of accelerated/ambient species.
