IN-FLIGHT PERFORMANCE OF THE VIRGO SOLAR IRRADIANCE INSTRUMENTS ON SOHO

The in-flight performance of the total and spectral irradiance instrum ents within VIRGO (Variability of solar IRradiance and Gravity Oscilla tions) on the ESA/NASA Mission SOHO (SOlar and Heliospheric Observator y) is in most aspects better than expected. The behaviour during the f irst year of operation of the two types of radiometers and the sunphot ometers together with a description of their data evaluation procedure s is presented.