Lifetime Measurements of the First 2+ States in Te116,118

The lifetimes of the first 2+ states in 116,118Te were measured by means of the recoil distance Doppler -shift technique with the CIAE-plunger coupled to a HPGe array via 107Ag(12C, 3n) and 110Pd(12C, p3n) reactions, respectively. The spectra are analyzed using the differential decay curve method. An improved precision for the lifetime of the 2+1 state in 118Te was obtained, tau(2+1) = 8.2(5) ps, as well as a first measurement of the 2+1 state in 116Te, tau(2+1) = 5.1(3) ps. The lifetime values complete the systematic data near midshell and contribute to the understanding of how quadrupole collectivity evolves in this mass region. The resulting B(E2, 0+1 -> 2+1 ) transitions strength are discussed in relation to the systematics of the previously reported B(E2, 0+1 -> 2+1 ) values in the Te isotopes and compared to the predictions of several models.