Formation, distribution and IR emission of dust in the clumpy ejecta of Type II-P core-collapse supernovae, in isotropic and anisotropic scenarios [SSA]

http://arxiv.org/abs/2209.14896


Large discrepancies are found between the observational estimates and the theoretical predictions, when exploring the characteristics of dust, formed in the ejecta of a core-collapse supernovae. We revisit the scenario of dust production in a typical supernova ejecta in the first 3000 days after explosion, with an improved understanding of the evolving physical conditions, and the distribution of the clumps. The generic, nonuniform distribution of dust within the ejecta was determined, and using that, the relevant opacities and fluxes were calculated. The dependence of the emerging fluxes on the viewing angle was estimated for an anisotropic, ellipsoidal geometry of the ejecta that imitates SN 1987A. We model the He-core from the centre to its outer edge as 450 stratified, clumpy, annular shells, uniquely identified by their distinct velocities and characterized by their variations in abundances, densities, and gas and dust temperatures. We find that the formation of dust starts between day 450 and 550 post-explosion, and it continues until about day 2800, however the first 1600 days is the most productive period. The total dust mass evolves from about 10-5 Msun at day 500 to 10-3 Msun at day 800, finally saturating at about 0.06 Msun. The masses of the O-rich dust (silicates, alumina) dominates the C-rich dust (amorphous carbon, silicon carbide) at all times; the formation of carbon dust is delayed beyond 2000 days post explosion. We show the opacities are the largest between days 800 and 1600, and the characteristic spectral features of O-rich dust species are suppressed at those times. The fluxes emerging along the smallest axes of the ellipsoidal ejecta are found to be the most obscured, while a viewing angle between 16 to 21 degrees with that axis appears to be in best agreement with the fluxes from SN 1987A at days 615 and 775.

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A. Sarangi
Fri, 30 Sep 22
39/71

Comments: Accepted for publication in Astronomy & Astrophysics (A&A)