Mean life of the 854 keV 02+ state in 74Se and the coexistence model

The mean life of the first excited 0₂⁺ state in ⁷⁴Se, only 219 keV above the first excited 2⁺ state at 635 keV, was measured to be 1.2±0.2 nsec, with delayed coincidence techniques. The 0₂⁺ state was populated by the decay of ⁷⁴Br produced via the ⁶⁰Ni(¹⁶O, pn)⁷⁴Br reaction. The extracted B(E2; 0₂⁺ → 20₁⁺) value is 14±2 s.p.u. which suggests that the 0₂⁺ state is collective. Application of a coexistence model in terms of spherical and deformed shapes is discussed for ⁷⁴Se.