Shock models indicate and observations show that in the infrared (IR), supernova remnants (SNRs) emit strongly in [Fe II] at 1.64 μm. Here, we report the results of a search for SNRs in NGC?6946 relying on [Fe II] 1.64 μm line emission, where we employed an adjacent [Fe II]Off filter to accurately assess the local continuum levels. For this study, we used the WIYN High Resolution Infrared Camera on the WIYN 3.5?m telescope to image NGC?6946 in broadbands J and H and narrowbands [Fe II], [Fe II]Off, Paβ, and PaβOff. From our search, we have identified 48 SNR candidates (SNRcs), 6 of which are coincident with sources found in prior radio, optical, and/or X-ray studies. The measured [Fe II] fluxes of our SNRcs range from 1.5 × 10–16 to 4.2 × 10–15 erg s–1 cm–2 and are among the highest of previously published extragalactic SNR [Fe II] fluxes. All of the candidates now need to be confirmed spectroscopically. However, the fact that we detect as many objects as we did suggests that [Fe II] can be used as an effective search tool to find extragalactic SNRs.
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