E1 and M1 transition strengths from two-quasiparticle structures in 168 Er
199122 pages
Published in:
- Nucl.Phys.A 533 (1991) 49-70
- Published: 1991
View in:
Citations per year
Abstract: (Elsevier)
Lifetime measurements in 168 Er were performed in the (n, γ) reaction using the generalized centroid-shift method with the following results: T 1 2 (JK π = 54 − at 1193.0 keV ) = 0.70±0.07 ns and T 1 2 (JK π = 33 3 − at 1999.2 keV ) = 0.44 −0.08 +0.12 ns . The size of some matrix elements of the ty 〈0 + | M 10 E |0 − 〉(Δ K = 0) and 〈0 + | M 1−1 E |1 − 〉(ΔK = 1) in 168 Eris estimat The evolution of the strenghts of E1 transitions linking some negative-parity bands with the ground band in N = 100 isotones with varying spin and neutron number is considered. For K -forbidden transitions, ΔK = 0 admixtures in the E1 matrix elements are found to be dominant in 168 Er and 170 Yb, while in 174 W ΔK = 1 admixtures become at least similarly important. In 168 Er, K π = 2 γ + admixtures in the ground band appear responsible for up to 45% of the size of the E1 transition matrix elements. A surprisingly small mixing (∼0.01%) of the structure { 7 2 − [523]− 1 2 + [411]} p (K π = 3 3 − ) into the s 7 2 + [633]− 1 2 − [5]} n (K π = 3 1 − ) and vice versa is found to account for the measured B (M1 strenght of the band-head 33 3 − → 33 1 − transition.- Nuclear reaction
References(0)
Figures(0)
Loading ...