THE ULTRAVIOLET CORONAGRAPH SPECTROMETER FOR THE SOLAR AND HELIOSPHERIC OBSERVATORY

The SOHO Ultraviolet Coronagraph Spectrometer (UVCS/SOHO) is composed of three reflecting telescopes with external and internal occultation and a spectrometer assembly consisting of two toric grating spectromet ers and a visible light polarimeter. The purpose of the UVCS instrumen t is to provide a body of data that can be used to address a broad ran ge of scientific questions regarding the nature of the solar corona an d the generation of the solar wind. The primary scientific goals are t he following: to locate and characterize the coronal source regions of the solar wind, to identify and understand the dominant physical proc esses that accelerate the solar wind, to understand how the coronal pl asma is heated in solar wind acceleration regions, and to increase the knowledge of coronal phenomena that control the physical properties o f the solar wind as determined by in situ measurements. To progress to ward these goals, the UVCS will perform ultraviolet spectroscopy and v isible polarimetry to be combined with plasma diagnostic analysis tech niques to provide detailed empirical descriptions of the extended sola r corona from the coronal base to a heliocentric height of 12 solar ra dii.