The LargE Area burst Polarimeter (LEAP): a NASA mission of opportunity for the ISS

The LargE Area burst Polarimeter (LEAP) is a proposed Compton scattering polarimeter that will, for the first time, measure the level of polarization for a significant number of GRBs with sufficient sensitivity to determine the magnetic field structure, composition, energy dissipation mechanism of GRB jets, and determine the prompt emission mechanism of GRBs. Once approved, LEAP will be deployed as an external payload on the International Space Station (ISS) where it will measure GRB polarization over the energy range from 50–1000 keV, perform GRB spectroscopy from 20 keV to 6 MeV, and self-sufficiently determine the source direction. LEAP is uniquely suited to fill a critical gap in our knowledge regarding GRBs, by exposing the underlying physics that governs astrophysical jets and the extreme environment surrounding newborn compact objects.