A balloon-borne infrared coronagraph and spectropolarimeter for magnetic field measurements of the solar corona

Abstract

The Coronal Spectropolarimeter for Airborne Infrared Research (CORSAIR) is a balloon-borne infrared coronagraph and spectropolarimeter funded by NASA's Heliophysics Low Cost Access to Space (H-LCAS) program and currently under development at Smithsonian Astrophysical Observatory (SAO). CORSAIR will make global, long-duration measurements of temperature, density, velocity and magnetic field in the solar corona by measuring the polarization state of five emission lines with wavelengths from 1 to 4 μm. The project incorporates various engineering challenges associated with making high-resolution, high-sensitivity observations spanning two octaves in wavelength in a low-cost package on a balloon-borne platform. CORSAIR is currently undergoing integration, alignment, testing, and calibration in preparation for its engineering qualification flight in late summer 2026. In this paper, we describe the scientific goals, instrument design, ongoing integration, and plans for the qualification flight.