The supernova remnant (SNR) candidate G 116.6 − 26.1 is one of the few high Galactic latitude (|b| > 15°) remnants detected so far in several wavebands. It was discovered recently in the SRG/eROSITA all-sky X-ray survey and also displays a low-frequency weak radio signature. In this study, we report the first optical detection of G 116.6 − 26.1 through deep, wide-field, and higher resolution narrowband imaging in H$\alpha$, $[\rm S\,{\small{\rm II}}]$ and $[\rm O\,{\small{\rm III}}]$ light. The object exhibits two major and distinct filamentary emission structures in a partial shell-like formation. The optical filaments are found in an excellent positional match with available X-ray, radio, and UV maps, can be traced over a relatively long angular distance (38 and 70 arcmin) and appear unaffected by any strong interactions with the ambient interstellar medium. We also present a flux-calibrated, optical emission spectrum from a single location, with Balmer and several forbidden lines detected, indicative of emission from shock excitation in a typical evolved SNR. Confirmation of the most likely SNR nature of G 116.6 − 26.1 is provided from the observed value of the line ratio [S ii] / H$\alpha$ = $0.56\, \pm \, 0.06$, which exceeds the widely accepted threshold 0.4, and is further strengthened by the positive outcome of several diagnostic tests for shock emission. Ourmore »
- Authors:
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publication Date:
- NSF-PAR ID:
- 10331291
- Journal Name:
- Journal of Glaciology
- Page Range or eLocation-ID:
- 1 to 9
- ISSN:
- 0022-1430
- Sponsoring Org:
- National Science Foundation
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