Multimessenger emission of GeV gamma-ray dark quasars

Highenergy neutrinos have been recently associated with astrophysical jets.Despite many efforts the details and microphysics of the neutrino emissionmechanism still elude us. Here we propose new observations of 10 radio bright,but gammaray dark, sources that were found to be positionally coincident withthe arrival directions of neutrinos. With the new XMMNewton observations wewill confidently measure their Xray spectrum for the first time, and constrainthe shape of their spectral energy distribution. This will allow us to confirm(or reject) them as neutrino emitters which will have significant implicationson both the location and neutrino emission mechanism in astrophysical jets aswell as our understanding of the highenergy emission processes in general truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]