DOI: 10.1017/pasa.2026.10255 ISSN: 1323-3580
Ejecta clumps revealed by study of reverse-shocked ejecta through MUSE integral field spectroscopy of SNR 0509-67.5
Priyam Das, Ivo Rolf Seitenzahl, Martin Laming, Gilles Ferrand, Simon Murphy, Ashley RuiterAbstract
We report the discovery of a spatially resolved clumpy ejecta structure in the reverse-shocked ejecta of SNR 0509–67.5, revealed through multiple faint and broad forbidden coronal emission lines in deep MUSE observations. We also identify two new broad coronal emission lines not reported before in this remnant, [Fe
xi
] 7894 Å and [Fe
x
] 6374.5 Å, which extend the set of previously reported [Fe
xv
] 7059.59 Å, [Fe
xiv
] 5302.86Å, [Fe
ix
] 8236.55 Å, [Ca
xv
] 5695Å, and [S
xii
] 7611.0 Å. Near-continuous ionisation states of Fe allow us to follow the ionisation progression behind the reverse shock. We use a 1D analytical model to evolve Fe charge states following reverse shock interaction to compare with observations, indicating the need for preshock clumping or over-density in order to reproduce the observed surface brightness of the [Fe
xiv
] line. Additionally, we report the spatially resolved distribution of ejecta clumps and show that reverse-shock interaction drives their compression and fragmentation. We also find a clear trend of decreasing velocity width with increasing Fe ionisation state, from the broadest [Fe
ix
] emission to the narrowest [Fe
xv
], with intermediate-ionisation species ([Fe
x
], [Fe
xi
], [Fe
xiv
]) showing intermediate widths. Finally, we compare our observations to a dynamically driven double-degenerate double detonation (D6) 3D remnant model at similar Fe and S ionisation states and conclude that the observed clumps are predominantly due to Rayleigh–Taylor instabilities.