Annales Geophysicae www.ann-geophys.net 0992-7689 1432-0576 26 10 2008 10.5194/angeo-26-3007-2008 http://www.ann-geophys.net/26/3007/2008/ http://www.ann-geophys.net/26/3007/2008/angeo-26-3007-2008.html http://www.ann-geophys.net/26/3007/2008/angeo-26-3007-2008.pdf 3007 3016 2008-10-15 Off-limb EUV observations of the solar corona and transients with the CORONAS-F/SPIRIT telescope-coronagraph V. Slemzin slem@sci.lebedev.ru O. Bougaenko A. Ignatiev S. Kuzin A. Mitrofanov A. Pertsov I. Zhitnik P.N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, Russia Sternberg Astronomical Institute, Moscow State University, Moscow, Russia The SPIRIT telescope aboard the CORONAS-F satellite (in orbit from 26 July 2001 to 5 December 2005), observed the off-limb solar corona in the 175 Å (Fe IX, X and XI lines) and 304 Å (He II and Si XI lines) bands. In the coronagraphic mode the mirror was tilted to image the corona at the distance of 1.1...5 <I>R</I>_sun from the solar center, the outer occulter blocked the disk radiation and the detector sensitivity was enhanced. This intermediate region between the fields of view of ordinary extreme-ultraviolet (EUV) telescopes and most of the white-light (WL) coronagraphs is responsible for forming the streamer belt, acceleration of ejected matter and emergence of slow and fast solar wind. We present here the results of continuous coronagraphic EUV observations of the solar corona carried out during two weeks in June and December 2002. The images showed a "diffuse" (unresolved) component of the corona seen in both bands, and non-radial, ray-like structures seen only in the 175 Å band, which can be associated with a streamer base. 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