What is powering the enigmatic HAWC source detected up to virgul100 TeV

2HWC J1928+177 is a bright Galactic gammaray source detected up to 100 TeV. Itis a peculiar HAWC source, as VERITAS and HESS failed to detect its gammarayemission and there is no SNR or PWN nearby. At the HAWC source position, thereis a variable Xray source, potentially associated with a bright IR source. Thenonthermal Xray spectrum and the lack of aperiodic variability indicate thatit is a TeV gammaray binary. XMM will determine the nature of the Xraycounterpart candidate, constrain its Xray variability pattern for future TeVobservations and search for other Xray sources. If the Xray counterpartcandidate is not a TeV gammaray binary and no diffuse Xray emission is found,the HAWC source would be the most remarkable dark accelerator with no counterpart below 10 TeV. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]