Lifetime measurement for the possible antimagnetic rotation band inPd101

Effects of proton angular momentum alignment on the two-shears-like mechanism inPd101

“…It can be seen that at the upbending region ( ω ∼ 0.45 MeV), the contributions from protons to the total angular momentum alignment J x are increased more than that of the neutrons, which indicates that this upbending mainly comes from the contribution of the protons. The present results are different from those obtained in Refs [33,34], where the increase of the angular momentum alignment is assumed to be from the alignment of one νg 7/2 neutron pair. In the present PNC-CSM calculation, the contributions from neutrons are much less considerable than those from protons.…”

“…1(a) that the four proton holes in 101 Pd are π9/2 + [404] (g 9/2 ) and π7/2 + [413] (g 9/2 ). The data show that the possible AMR band in 101 Pd is the lowest lying negative parity band, which is assigned as νh 11/2 [33,34]. It can be seen from Fig.…”

“…Therefore, in the following investigation, adiabatic calculations for the ν1/2 − [550] band in 101 Pd will be performed and the level crossings in protons and neutrons appear automatically with increasing rotational frequency. Figure 2 shows the experimental (solid circles) and calculated kinematic MOI's J (1) with (black solid line) [33,34], the upbending around ω ∼ 0.45 MeV is interpreted as alignments of two g 7/2 quasi-neutrons. In the following, the upbending mechanism in this band will be investigated.…”

Band structures in Pd101

“…These observations are interpreted in the framework of semiclassical particle rotor model (PRM) calculations as antimagnetic rotation (AMR) based on closing of the oppositely aligned g 9/2 proton holes in the π(g 9/2 ) −2 ⊗ ν[h 11/2 (g 7/2 /d 5/2 ) 2 ] double-shears configurations [45]. The aforementioned observations differ significantly from the DSAM based lifetime measurements in band B3 by Sugawara et al [22,23], wherein the decreasing trend in the B(E2) values has been reported in the lower portion in band B3 with 19/2h ≤ I ≤ 31/2h and interpreted as AMR arising due to closing of the shears with the proton blade of each shear consisting of angular momentum vector of two πg 9/2 holes [23,24]. It is unlikely as making symmetric shears out of (πg 9/2 ) −4 has to be very selective and involves strong proton-proton interaction strength.…”

“…The quasirotational bands built on the νd 5/2 , νg 7/2 , and νh 11/2 orbitals, and the related configurations have been reported in 101 Pd. Sugawara et al have reported the lifetime measurements in the νh 11/2 band and the observed decreasing trend of the B(E2) rates has been interpreted as antimagnetic rotation (AMR) [23,24]. The present work reports the extended level scheme of 101 Pd nucleus investigated using a high efficiency Compton-suppressed array.…”