emission is consistent with that of the PWN at high energies, we first assume that the $\gamma$-ray emission comes only from the PWN. We model its spectrum as a power law and we perform a likelihood fit where the spectral parameters of the PWN, those of the nearest point source, the Galactic and isotropic diffuse emissions are free during the fit. The spectral parameters of the other sources are fixed to their best-fit values since they are further than $\sim$ 2° from G326.3$-$1.8. The fit gives a TS value of TS = 593.4, as reported in Table \[tab:LL\], with the number of additional free parameters compared to the model without source.

[l|ccc]{}

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Spatial models & TS & N$_{\rm{dof}}$ & TS$_{\rm{PWN}}$\

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Radio PWN & 593.4 & 2 & —\

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Point source & 503.3 & 4 & —\

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Point source + radio PWN & 661.4 & 6 & 158.1\

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Disk & 681.8 & 5 & —\

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Disk + radio PWN & 694.8 & 7 & 13.0\

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Radio SNR & 667.3 & 2 & —\

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Radio SNR + radio PWN & 683.0 & 4 & 15.7\

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SNR mask & 670.3 & 2 & —\

