HiRES: high resolution extreme ultraviolet spectroheliometer

Abstract

The HiRES sounding rocket payload is designed to obtain very high spatial, spectral, and temporal resolution images of the solar chromospheric and coronal plasmas in the extreme ultraviolet (EUV) wavelength range from 500 to 650 Å. The instrument consists of a 450 mm f/15 Gregorian telescope feeding a 1-m normal incidence stigmatic spectrometer. The stigmatic spectrometer utilizes a toroidal diffraction grating formed by a unique elastic substrate deformation technique in order to achieve simultaneous spatial and spectral focusing at two points on the detector plane. Spatial resolution on the order of 0.4 arcsecond across a 3×3 arcmin2 field of view is obtained. Temporal resolution of the order of milliseconds is achieved by the use of an advanced imaging Multi-Anode Microchannel Array (MAMA) detector. A hydrogen-alpha 6562.8 Å camera and a 0.25-m EUV solar irradiance spectrometer are also included in the payload.