The first T=2 state in ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ ($E_x$=27.483 MeV) has been studied by means of the isospin-forbidden resonance in the reaction d${+\mathrm{}}^6$Li→α+α. Angular distributions of the cross section and of the four analyzing powers for the reaction ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$(d→,α${)\mathrm{}}^4$He have been measured at energies above, below, and on resonance. Off-resonance analyzing power measurements have also been obtained for ${}_{}{}^2{}_{}{}^{}\mathrm{H}$${(}^6$Li→,α${)\mathrm{}}^4$He. Because of the symmetry properties of the reaction, the number of independent collision matrix elements is fairly small, and this makes it possible to determine the matrix elements directly by fitting the data. By comparing the matrix elements, one can determine partial widths (${\Gamma }_0$ and ${\Gamma }_2$) for decay of the ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ state into d${+\mathrm{}}^6$Li states with channel spin 0 and 2. The measured ratio of the partial widths is ${\Gamma }_2$/${\Gamma }_0$=0.322±0.091.

• Received 27 January 1986

DOI:https://doi.org/10.1103/PhysRevC.34.401