X-ray/optical/radio Observations of a Resolved Supernova Remnant in Ngc 6822

The supernova remnant (SNR), Ho 12, in the center of the dwarf irregular galaxy NGC 6822 was previously observed at X-ray, optical, and radio wavelengths. By using archival Chandra and ground-based optical data, we found that the SNR is spatially resolved in X-rays and optical. In addition, we obtained a ∼ 5 resolution radio image of the SNR. These observations provide the highest spatial resolution imaging of an X-ray/optical/radio SNR in that galaxy to date. The multi-wavelength morphology, X-ray spectrum and variability, and narrow-band optical imagings are consistent with a SNR. The SNR is a shell-shaped object with a diameter of about 10 (24 pc). The morphology of the SNR is consistent across the wavelengths while the Chandra spectrum can be well fitted with a nonequilibrium ionization model with an electron temperature of 2.8 keV and a 0.3–7 keV luminosity of 1.6×1037 ergs s−1. The age of the SNR is estimated to be 1700 − 5800 years. Subject headings: galaxies: individual (NGC 6822) — supernova remnants — X-rays: ISM