The ${}^{12}\mathrm{C}({}^3\mathrm{He},d){}^{13}\mathrm{N}^{*}$ reaction is studied in an experiment with a high-resolution magnetic spectrograph, in coincidence with protons detected in silicon detectors near the target. This allows for the observation of angular correlation patterns between the proton transfer and proton decays from populated unbound resonances. A formalism describing the spin polarization of direct reactions is developed to analyze these correlations, and is verified on the known directionally asymmetric decay distributions arising from parity mixing in the ${}^{13}\mathrm{N}({\frac{3}{2}}^{-},{\frac{5}{2}}^{+})$ doublet. The same formalism is used to study the decays from the continuum-aligned, broad $3/2^{+}$ resonance at 7.9 MeV excitation energy, which arises from superradiant coupling. The observed asymmetric angular correlation patterns are approximately reproduced by adding an “artificial” $3/2^{-}$ resonance with strength equal to that of the reaction formalism. This parity-mixing approach serves as a first approximation to a more advanced reaction model of rapid reaction and decay sequences.

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• Breakup reactions
• Direct reactions
• Lifetimes & widths
• Models & methods for nuclear reactions
• Optical, coupled-channel & distorted wave models
• Proton emission
• Transfer reactions
• 6 ≤ A ≤ 19