No abstract

We investigated two isotones (N = 74) -129 Cs and 127 I in the mass region 130 -both with moderate deformation, exhibiting signature splitting in their positive-parity bands based on the πg 7/2 configuration. Interestingly, signature inversion occurs in 127 I at low spin (19/2 + ), while no inversion has been observed for 129 Cs. Here we present some new results on the reduced transition probability B(E2) for states belonging to 127 I. The lifetimes in picoseconds were measured using the Doppler Shift Attenuation Method (DSAM). We utilized the single quasi-particle rotor model to theoretically describe our results, which suggest higher deformation and triaxiality (ε 2 = 0.23, γ = 28 • in Lund convention) for 127 I than for 129 Cs (ε 2 = 0.15, γ = 18 • ).