EXPLORING THE CORONA OF MRK 926

We propose to observe Mrk 926 for 35 ks with XMM and 100 ks with NuSTAR toexplore the Comptonization spectrum of this bright Seyfert 1 galaxy. Previousanalyses of nonsimultaneous observations have found a lower limit of the highenergy cutoff of 510 keV, bringing it in disagreement by the temperature limitset by runaway pair production. With the proposed observations we will test,whether Mrk 926.s spectrum is consistent with thermal Comptonization or not. Ifit is, we can study its Comptonization spectrum from the UV to the hard Xraysand would obtain key information on the properties of coronae typical forSeyferts. However, if we find that the temperature is inconsistent with thermalComptonization, we can use this dataset to understand which other process could be responsible. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]