Ground-based multichannel photometry of integral sunlight has been obtained at Izaña (Tenerife) during three months in 1984 with a photometer built at ESTEC...

The small imaging photometer of the VIRGO (Variability in IRradiance and Gravity Oscillations) investigation on ESA's SOHO mission is presented. This instrument...

The VIRGO Experiment (Variability of solar IRradiance and Gravity Oscillations) contains two types of active cavity radiometers for monitoring of the solar...