Establish whether the potential fourth excess is a distinct gamma-ray source

Establish whether the potential fourth extended gamma-ray excess in the DA 495 region constitutes a distinct source, given that its inferred flux, spatial extension, and other properties depend strongly on the Galactic diffuse-emission model.

Background

The analysis finds a residual excess near the DA 495 region that can be modeled as a fourth extended source under some Galactic diffuse-emission assumptions. However, the source properties differ substantially depending on whether the diffuse-emission normalization is fixed or allowed to vary. The authors therefore do not regard the source identification as established, although they mention possible supernova-remnant and TeV-halo counterparts.

References

Therefore, we consider it premature to claim it as a distinct source, though potential counterparts include SNRs G066.0-0.0 and G067.6+0.9 \citep{2013MNRAS.431..279S}, and a possible TeV halo associated with PSR J1958+3033 \citep{2018ApJ...869..181P}.

— TeV Gamma-Ray Emission in the DA 495 Region from HAWC Observations of J1952+2924, J1954+2837, and J1958+2848  (2610.13771 - Alfaro et al., 9 Oct 2026) in Section 5.1, “Potential Fourth Source?”