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A30 belongs to a class of planetary nebulae identified as "born-again",containing dense, hydrogen-poor ejecta with extreme abundance discrepancyfactors (ADFs), likely associated with a central binary system. We presentintermediate-dispersion spectroscopy of one such feature-the J4 equatorialknot. We confirm the apparent physical and chemical segregation of the polarand equatorial knots observed in previous studies, and place an upper limit onthe ADF for O$^{2+}$ of 35, significantly lower than that of the polar knots.These findings further reinforce the theory that the equatorial and polar knotsoriginate from different events.

Abundance Analysis of the J4 Equatorial Knot of the Born-again Planetary Nebula A30