The Astrophysical Journal · 1989 · 17 citations · 0 references
Natural SciencesAstronomyPhysicsAstrophysicsObservational AstronomySolar AstronomyPhotometric SystemsSolar Active RegionsSolar IrradianceSolar ObservationsSolar PhysicsSolar RadiationIrradiancePhotometrySolar ConstantSolar Irradiance SpectroscopySolar Irradiance VariabilitySolar Physics ObservationsSunspot SpectroscopyTotal Solar Irradiance
A photometric telescope constructed to obtain photometric sunspot areas and deficits on a daily basis is described. Data from this Cartesian full disk telescope (CFDT) are analyzed with attention given to the period between June 4 and June 17, 1985 because of the availability of overlapping sunspot area and irradiance deficit data from high-resolution digital spectroheliograms made with the San Fernando Observatory 28 cm vacuum solar telescope and spectroheliograph. The CFDT sunspot deficits suggest a substantial irradiance contribution from faculae and active region plage.