A HIGH RESOLUTION INTEGRAL FIELD SPECTROGRAPH FOR THE EUROPEAN SOLAR TELESCOPE

This paper presents the proposal of a high resolution, integral field spectrograph that is currently being designed for the 4-meter aperture European Solar Telescope that will be located in the Canary Islands. This instrument is optimized to study the solar chromosphere and photosphere to allow the investigation of several phenomena concentrated within these two layers. It will be able to observe simultaneously a bidimensional field of view of 80 arcsec2 that is reorganized, using an integral field unit, into 8 long slits of 200 arcsec length by 0.05 arcsec width. It will have the capability to observe different layers of the Sun at the same time due to its multi-wavelength capability that allows the observation of 5 visible and 3 near-infrared wavelength intervals from 3900 to 23,000 A, with a spectral resolution of about 300,000. The designed instrument is telecentric and presents an optical quality limited by diffraction.