The following document lists the file abstract/AQUIRREN_RAPIDVAR.abs
from catalogue VI/111.
A plain copy of the file
(without headers/trailers) may be downloaded.
We propose to monitor one extreme BL Lac object (0716+714 or 1749+701, depending on launch date) for 12 days with a sampling of two observations per day. Both objects are known to show strong intraday varibility both in the radio and optical wavelength domains; for 0716+714 there are strong indications that these variations are correlated between the radio and optical. Similar correlations seem to exist in 1749+701 and a number of other sources, but are extremely difficult to prove without coverage of the infrared range. Rapid variations present a serious challenge to the standard relativistic jet model, since they imply either Doppler factors as high as 200, or exotic (e.g. stimulated) emission mechanisms. By obtaining light curves at 6 wavelengths ranging from 5 to 160 micron we will be able to answer the following questions: What is the wavelength dependence of the variability amplitude? Is there a break at mid-IR wavelengths? Are there correlated variations through the radio - IR - optical range? Are there time delays between the light curves at different wavelengths? To what extent (if any) are the radio light curves affected by inter- stellar scattering, which might mimic intrinsic variations? We will thus be able to model in much more detail than presently possible the physical conditions in the compact jets of blazars, and to understand the radiation mechanisms responsible for the emission coming from these regions.