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   71120
   The BL Lac object PKS2155-304 is one of the brightest and most variable
   blazars. The X-ray emission is most likely due to the synchrotron
   emission. To study the energy dependence of the light curve during
   flares is the only mean to perform quantitative studies of the
   acceleration mechanism in blazar jets. Previous campaigns revealed
   variability with clear energy dependece but did not have sufficient
   sampling to permit firm conclusions about the conditions in the jet. We
   propose to monitor PKS2155-304 for 400 ks to obtain the continuous
   light curve from the source. During this interval, optical and TeV
   observations will be scheduled at facilities at many diverse locations
   to obtain nearly continuous light curves in all wavelengths.
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