IS THE BRIGHTEST GAMMA-RAY SOURCE ABOVE 100 TEV POWERED BY BOW SHOCK PULSAR WIND NEBULAOR HADRONIC INTERACTION?

THE PROPOSED NUSTAR OBSERVATION WILL PROVIDE A UNIQUE OPPORTUNITY TO IDENTIFY THE BRIGHTEST GALACTIC GAMMA-RAY SOURCE ABOVE 100 TEV 2HWC J1825-134 (HESS J1826-130). IT IS STILL UNCLEAR WHETHER THE TEV GAMMA-RAY EMISSION HAS LEPTONIC OR HADRONIC ORIGIN. IN THE LEPTONIC SCENARIO THE PWN OF THE FAST-MOVING PULSAR PSR J1826-1256 EMITS TEV GAMMA-RAYS VIA INVERSE COMPTON SCATTERING THROUGH VERY ENERGETIC ELECTRONS AT ~300 TEV. IN THE HADRONIC SCENARIO RELATIVISTIC PROTONS FROM THE NEARBY SUPERNOVA REMNANTS BOMBARDING THE MOLECULAR CLOUDS PRODUCE TEV GAMMA-RAYS. OUR MULTI-WAVELENGTH SED MODELS PREDICT DISTINCT X-RAY SPECTRAL INDICES BETWEEN THE TWO SCENARIOS. NUSTAR'S BROAD-BAND SPECTROSCOPY WILL TEST WHETHER THE BOW-SHOCK PWN OR HADRONIC INTERACTIONS POWER THE BRIGHTEST GALACTIC HAWC SOURCE.