| dc.description.abstract | Supernova remnant SN386(G7.7-3.7) presented captivating attention for multi-wavelength observation. In this study, we investigated the structural characteristics of G7.7-3.7 with higher resolution MeerKAT observation at 1284 MHz, revealing intricate details of its morphology and emission mechanisms. MeerKAT observations revealed G7.7-3.7 as an almost circular structure with filamentary features, manifesting in various blowouts. The western boundary exhibited a strong, bright blowout, while the southern perimeter showed extended bright filaments with feather-like structures, seemingly disconnected from the western blowout. Moreover, the eastern region presented a faint blowout with a centralized bright point source, while faint elongated filaments traversed the northwest, linked the eastern point source and western blowout, and progressed outward uniformly. Spectral index analysis indicated a steep spectrum (𝛼 ranged ∼ 0 to ∼3), suggesting a combination of synchrotron and a few traces of thermal emissions at the edges of bright blowouts. Bright blowouts with a less steep spectrum ranging from ∼-0.5 to ∼-1.5 were dominated by shock-accelerated particles encountering irregularities and weakening in magnetic fields. Spectral index values close to 𝛼 = 0 showed the presence of traces of thermal emissions from shock-heated gases, especially at the edge of the bright blowout. However, the faint emissions along the filaments connecting the eastern and western blowouts with a very steep spectral index of ∼-3 comprised synchrotron emissions from aged particles that had dissipated energy due to turbulent re-acceleration. Analysis of MeerKAT and VLA data gave an expansion of Δ𝜃 = 9 ± 0.45 arcsec over a period of Δt = 31.907 yr corresponding to an expansion rate 𝜃 = 0.282 ± 0.014 arcsec yr−1. The data recorded a shock speed of 5883 ± 294 km s−1 and an age of 1636 ± 115 years. The revised age fitted with the explosion event of 386 CE and the observed data in 2023. Furthermore, our multi-wavelength investigation unveiled an intriguing structure within the southern radio blowout exhibiting a convergence of features such as the bright radio blowout, a prominent X-ray arc, and two faint optical filaments aligned with the X-ray bright arc. We attributed the bright radio blowouts to the non-uniform mass outflow from the localized high-density population of the shock-accelerated particles and the weakening of magnetic fields along its perimeter. Thermal emissions traces along the edges of blowouts resulted from shock-heated gases intensifying in the south due to the presence of high-density ISM. Thus, we proposed that the supernova of G7.7-3.7 occurred in an environment of varying densities of interstellar medium (ISM). Consequently, this environment facilitated X-ray emissions and the formation of faint optical filaments due to collisions with the ISM and the circumstellar materials from the progenitor star, respectively. Our findings shed light on the complex interplay of physical processes within G7.7-3.7, offering valuable insights into the dynamics and evolution of supernova remnants. | en_US |
