A&A Supplement series, Vol. 128, March II 1998, 589-598
Received June 17; accepted July 29, 1997
Send offprint request: F. Cavallini
Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze, Italy
A new instrument for solar bidimensional spectroscopy, the Italian Panoramic Monochromator (IPM), has been recently installed on the Télescope Heliographique pour l'Étude du Magnétisme et des Instabilités de l'atmosphère Solaire (THEMIS), the French-Italian solar telescope built in Tenerife (Canary Islands). On a square field , this instrument allows one to obtain monochromatic images of the solar surface with high spectral resolution ( 256000 at 5500 Å), preserving all the spatial resolution delivered by the telescope (). The wavelength stability of the instrumental profile is very high, the maximum drift in 10 hours amounting to about 10 ms-1.
keywords: instrumentation: interferometers -- instrumentation: spectrographs -- Sun: photosphere -- Sun: chromosphere