Energy density of TeV sources calculated using two different approaches. The top panels are calculated as ${\epsilon }_{\mathrm{e}}=\dot{E}{\tau }_c/V$, and the bottom panels are calculated following the approach in Section 3.2 of Giacinti et al. (2020). The newly identified pulsar halo associated with PSR J0622+3749 (Aharonian et al. 2021), indicated by a star, is shown along with the Geminga halo and Monogem halo (Abeysekara et al. 2017a). The circles representing several γ-ray PWNe are based on data from Giacinti et al. (2020), and γ-Cygni under different distance assumptions is shown as squares.