MULTIFREQUENCY OBSERVATIONS OF THE OPTICALLY-ACTIVE RADIO-QUIET QUASAR GQ COMAE .2. ULTRAVIOLET, OPTICAL, AND INFRARED CONTINUUM VARIABILITY

This paper summarizes the data and preliminary results of a 3 yr long project to monitor the continuum variability of GQ Comae (PG 1202 + 28 1) from 0.12 mum to 3.5 mum. Substantial variability in the optical/ul traviolet flux was observed. The variability is examined using a geome trically thin accretion disk model. The model is able to reproduce the variations, but contains problems with physical consistency. A compar ison of the optical/ultraviolet data and the infrared data indicates t hat the flux at 2.2 mum did not respond to the optical-ultraviolet con tinuum increase until nearly 250 days after the outburst and suggests that the variable flux at this wavelength is due to heated dust. We mo del the infrared emission with a dust component which is heated by the radiation from the accretion disk. We show that a simple model using a disklike distribution Of heated dust grains can explain most of the infrared variability in a natural way.