3HWC J0631+107/LHAASO J0631+1040: A TeV Halo Powered by the Pulsar J0631+1036?

PSR J0631+1036 is a middle-aged pulsar with properties similar to those of the nearby Geminga pulsar. It is bright in gamma-rays, and has been noted as the only source possibly associated with the TeV source 3HWC J0631+107 (also the LHAASO J0631+1040). For understanding the nature of the TeV source, we analyze the GeV gamma-ray data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope for the source region. We are able to remove the pulsar's emission from the region from timing analysis, and find that the region is rather clean without possible GeV gamma-ray emission present as the counterpart to the TeV source. By comparing this pulsar to Geminga and considering the spectral feature of the TeV source, we argue that it is likely the TeV halo powered by the pulsar.