Lifetime of the 3.56-Mev State inLi6

Abstract

An upper limit for the mean life of the 3.56-Mev state in ${\mathrm{Li}}^6$ of 5×${10}^{-14\mathrm{}}$ sec has been established by a Doppler shift method. This supports the $0^{+}$, $T=1\mathrm{}$ assignment for this level. It has also been established by a Doppler shift technique that the angular distribution of the recoil alphas arising from the ${\mathrm{Be}}^9(p, \alpha ){\mathrm{Li}}^{6*}\left(\gamma \right){\mathrm{Li}}^6$ reaction is symmetric about 90° in the center-of-mass system at the resonant bombarding energy of 2.56 Mev. At 2.93-Mev bombarding energy the angular distribution of the alphas is peaked forward of 90°.