Modeling the Saddle-like GeV-TeV Spectrum of HESS J1809-193: $\gamma$-Rays Arising from Reverse-Shocked Pulsar Wind Nebula?

Jiaxu Sun, Yang Chen, Yiwei Bao +2

Evolution of pulsar wind nebulae (PWNe) could be expected to leave imprints in $\gamma$-rays. We suggest that intriguing GeV-TeV spectral energy distribution (SED) of HESS J1809$-$193 a…