000			03848nam a22002057a 4500
003			KE-MeUCS
005			20260609164955.0
008			260609b |||||||| |||| 00| 0 eng d
020			_a
040			_cKE-MeUCS _dKE-MeUCS
050			_aQB843.S9.M8 2025
100			_aMwaniki, Patrick Njoroge
245			_aMeerkat-Based Multi-Wavelength Study of Supernova Remnant SN386 (G7.7-3.7)/ _c Patrick Njoroge Mwaniki
260			_aMeru: _bMeru University of Science and Technology, _c2025.
300			_aix, 75p.
500			_aIncludes Reference
520			_aSupernova 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 show cased extended bright filaments with feather-like structures, seemingly disconnected from the western blowout. Moreover, the eastern region presented a faint blowout with a cen tralized 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 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 explo sion 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 forma tion 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 evo lution of supernova remnants.
856			_uhttps://repository.must.ac.ke/handle/123456789/1638
942			_2lcc _cTH _tMMS
999			_c93774 _d93773