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The RS CVn binary system HR1099 (V711 Tau) was observed by the Extreme Ultraviolet Explorer (EUVE) satellite as a calibration target on 1992 October 22-24. Emission from the system is detected in both the short (75-175 \AA) and medium (150-370 \AA) wavelength EUVE spectrometers. No stellar signal is seen in the long wavelength spectrum. Over 20 coronal and transition region emission lines are present, along with continuum emission from hot ($\sim$ 10$^{7}$ K) coronal plasma at the shorter wavelengths. The short wavelength spectrum is dominated by coronal lines from the hot 10$^{7}$ K coronal component; the highest excitation line definitely present is Fe XXIII 132.8 \AA. The medium wavelength spectrum is dominated by He II 304 \AA\ from transition region (10$^{5}$ K) plasma. The volume emission measure (VEM) distribution of HR1099 is determined over the temperature range 10$^{5}$ to over 10$^{7}$ K. This distribution is compared with previous broadband X-ray estimates of the coronal temperature and VEM for HR1099. The implications of these data for the likely coronal structure of active binaries like HR1099 are discussed.
This work is supported by NASA grant NAGW-2904 to the University of Colorado. We thank the EGO Center staff at CEA for their assistance.