We investigate supernova mixtures reproducing isotopic ratios of individual presolar grains from supernovae. We divide the supernova ejecta of 3.3, 4, 6, and 8 M He star models into seven layers, i.e., the Ni, Si/S, O/Ne, C/O (3.3 and 4 M models) or O/C (6 and 8 M models), He/C, and He/N layers. Then, we seek the mixing ratios of the mixtures reproducing the isotopic ratios of 12C/13C, 14N/15N, 16O/17O, 16O/18O, 26Al/27Al, 29Si/28Si, 30Si/28Si, and 44Ti/48Ti as many as possible measured in a low density graphite grain KE3a‐322. Six isotopic ratios of the grain are reproduced by two mixtures of 4 M model and a mixture of 6 M model. The main component of the mixtures is the He/N layer to reproduce 12C/13C ratio and to be the C/O ratio of the mixtures slightly larger than unity. However, 14N/15N is not reproduced by the mixtures. Isotopic ratios of 16O/17O and 16O/18O are reproduced by containing the He/C‐ and He/N‐layer components in the mixtures. The Si/S layer should be contained to reproduce the excess of 28Si and the mixing ratio is smaller than 1 × 10−4 for this grain. The Ni layer can be contained to reproduce 26Al/27Al. However, too much contribution of the Ni layer raises 44Ti/48Ti in mixtures.

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