SIMBAD references

Recent X-ray studies have shown that supernova shock models are unable to satisfactorily explain X-ray emission in the rim of the Cygnus Loop. In an attempt to account for this "anomalously" enhanced X-ray flux, we fit the region with a model including theoretical charge exchange (CX) data along with shock and background X-ray models. The model includes the CX collisions of O^8 +^, O^7 +^, N^7 +^, N^6 +^, C^6 +^, and C^5 +^ with H with an energy of 1 keV.u^–1 (438 km/s). The observations reveal a strong emission feature near 0.7 keV that cannot fully be accounted for by a shock model, nor the current CX data. Inclusion of CX, specifically O^7 +^ + H, does provide for a statistically significant improvement over a pure shock model.