Perhaps this helps…

The Astronomical Journal, 148:41 (15pp), 2014 September doi:10.1088/0004-6256/148/3/41

Shock models indicate and observations show that in the infrared (IR), supernova remnants (SNRs) emit strongly

in [Fe ii] at 1.64μm. Here, we report the results of a search for SNRs in NGC 6946 relying on [Fe ii] 1.64μm 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.

Perhaps this helps…

The Astronomical Journal, 148:41 (15pp), 2014 September doi:10.1088/0004-6256/148/3/41

Shock models indicate and observations show that in the infrared (IR), supernova remnants (SNRs) emit strongly

in [Fe ii] at 1.64μm. Here, we report the results of a search for SNRs in NGC 6946 relying on [Fe ii] 1.64μm 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.

Good find by Eric.

1.64 microns is in the middle of the H band, which has the added advantage of being where most adaptive optics systems are optimised. This would help to pick out smaller, more distant, or more crowded SNRs.

it depends on the prefessional parctice you have for observations.you can try to use X-ray,optical, radio data to your spesific SNR.  if you do not have any idea and wondering if there exists any SNR please read our paper with M.Vucetic in my publication list,may give you some idea.