The Breakup Energy ofBe8

The ${\mathrm{B}}^{11}(p, \alpha ){\mathrm{Be}}^8$ reaction has been used as a source of ${\mathrm{Be}}^8$ for the measurement of the $Q$ for ${\mathrm{Be}}^8\to 2\alpha$. Protons of several Mev energy were used to bombard various thin boron targets and the breakup alphas were observed at ∼135° to the proton beam. A spherical electrostatic analyzer was used for measurement of the alpha energy. A value of 94.5±1.4 kev was found for the breakup energy.