Azimuthal distributions of fission fragments and α particles emitted in the reactionsAr36+238U atE/A=20 and 35 MeV andN14+238U atE/A=50 MeV

Azimuthal correlations between coincident fission fragments and α particles were measured for the reactions ${}_{}{}^{36}{}_{}{}^{}\mathrm{Ar}$ ${+}^{238}$U at E/A=20 and 35 MeV and ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ ${+}^{238}$U at E/A=50 MeV. At all energies, coplanar emission is enhanced. The azimuthal distributions for fission fragments and α particles are decoupled using a simple parametrization. Both azimuthal distributions are highly anisotropic at lower incident energies; these anisotropies decrease with energy. At the highest incident energies, energetic α particles emitted at large transverse momenta appear to be more suited than fission fragments to tag the orientation of the entrance channel reaction plane.