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Instabilities and Mixing in SN 1993J

K. Iwamoto·T. R. Young·N. Nakasato·T. Shigeyama·K. Nomoto·I. Hachisu·H. Saio
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Abstract

Rayleigh-Taylor (R-T) instabilities in the explosion of SN 1993J are investigated by means of two-dimensional hydrodynamical simulations. It is found that the extent of mixing is sensitive to the progenitor's core mass and the envelope mass. Because the helium core mass (3 - 4 \ms) is smaller than that of SN 1987A, R-T instabilities at the He/C+O interfaces develop to induce a large scale mixing in the helium core, while the instability is relatively weak at the H/He interface due to the small envelope mass. The predicted abundance distribution, in particular the amount of the \ni~ mixing, is compared with those required in the theoretical light curves and the late time optical spectra. This enables us to specify the progenitor of SN 1993J in some detail.

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K. Iwamoto, T. R. Young, N. Nakasato, T. Shigeyama, K. Nomoto, I. Hachisu, H. Saio. 1997-01-15. Instabilities and Mixing in SN 1993J. https://doi.org/10.1086/303729

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