1240032

We propose a 500 ks target of opportunity INTEGRAL observation of a blazar in outburst as detected by the new FACT TeV gamma-ray telescope blazar monitoring program supplemented by pre-outburst snapshots and follow-up monitoring with Swift. Bright TeV gamma-ray flares have been detected frequently from blazars such as Mrk 501 and Mrk 421 but complete time-resolved information of the multiwavelength spectra covering the complete outburst are not available. Leptonic models for TeV flares predict simultaneous flux increases in the X-ray and in the gamma-ray band while lepto-hadronic models show a complex variability pattern in these energy bands depending on the dominant process responsible for the gamma-ray emission. Other types of TeV flares which cannot be explained with current models are also observed: orphan flares which show variability in gamma-rays only and flares with time lags between both bands. Most existing data sets of flaring behaviors lack detailed pre- and post-flare light curves and spectra as well as continuous TeV monitoring.The here proposed observations 1) are triggered on bright gamma-ray flares 2) yield simultaneous data in the optical/UV X-ray GeV- and very-high gamma-ray bands and 3) contain pre- and post-flare source state information. This type of ToO observations become feasible for the first time with the start of the FACT blazar monitoring program. [truncated! Please see actual data for full text]