The experimental large fluctuation in odd-even differences in moments of inertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC) method for treating the cranked shell model with ...The experimental large fluctuation in odd-even differences in moments of inertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC) method for treating the cranked shell model with monopole and quadrupole pairing interactions. PNC calculations show that the large odd-even difference in moments of inertia mainly comes from the interference contributions j(μν) from particles in high j intruder orbitals μ and ν quite near the Fermi surface, which have no counterpart in the BCS formalism. The effective monopole and quadrupole pairing interaction strengths are determined to fit the experimental odd-even differences in binding energies and bandhead moments of inertia. The experimental results for the variation of moments of inertia with rotational frequency ω are reproduced well by the PNC calculation. The nearly identical experimental moments of inertia between 236 U(gsb) and 238 U(gsb) at low frequencies hω≤ 0.20 MeV are also reproduced quite well.展开更多
A comprehensive analysis of the superdeformed bands observed near A≈190 indicates that there exist systematic odd-even differences in the moments of inertia similar to that observed in normally deformed nuclei, which...A comprehensive analysis of the superdeformed bands observed near A≈190 indicates that there exist systematic odd-even differences in the moments of inertia similar to that observed in normally deformed nuclei, which can be considered as compelling evidence for pairing and blocking effect in super-deformed nudei. With increasing rotational frequency the odd-even differences become weaker and weaker due to the Coriolis anti-pairing effects. Particularly, the odd-even differences in the dynamic moments of inertia become obscure when hω≥2 MeV, and in certain cases there emerges nearly identical value of J(2) for some neighboring nudei. However, the odd-even differences in the kinematic moments of inertia still remain to certain extent at the highest frequencies.展开更多
The difference in the bandhead moments of inertia between the superdeformed (SD) band 194Hg(1) and the two-quasiparticle SD bands 194Hg(2,3) was investigated using the particle-number-conserving treatment for the cran...The difference in the bandhead moments of inertia between the superdeformed (SD) band 194Hg(1) and the two-quasiparticle SD bands 194Hg(2,3) was investigated using the particle-number-conserving treatment for the cranked shell model Hamiltonian, and the pairing interaction strength in SD nuclei is estimated to be much weaker than that in normally deformed nuclei.展开更多
In the particle-number-conserving treatment of the cranked shell model Hamiltonian (blocking effect being taken into account exactly), the calculated even-odd differences in moments of inertia show large variation and...In the particle-number-conserving treatment of the cranked shell model Hamiltonian (blocking effect being taken into account exactly), the calculated even-odd differences in moments of inertia show large variation and depend sensitively on the location and Coriolis response of the blocked levels. The moments of inertia of the 170Yb, 171Lu [404] 7/2, [402] 5/2, [514] 9/2 and 171Yb [512] 5/2, [633] 7/2 bands at low spin are calculated and the experimental data are reproduced very well. No free parameter was involved in the calculation. The reason of the discrepancy between the observed "identical bands" at low spin and the BCS prediction is discussed.展开更多
文摘The experimental large fluctuation in odd-even differences in moments of inertia of deformed actinide nuclei is investigated using the particle-number conserving (PNC) method for treating the cranked shell model with monopole and quadrupole pairing interactions. PNC calculations show that the large odd-even difference in moments of inertia mainly comes from the interference contributions j(μν) from particles in high j intruder orbitals μ and ν quite near the Fermi surface, which have no counterpart in the BCS formalism. The effective monopole and quadrupole pairing interaction strengths are determined to fit the experimental odd-even differences in binding energies and bandhead moments of inertia. The experimental results for the variation of moments of inertia with rotational frequency ω are reproduced well by the PNC calculation. The nearly identical experimental moments of inertia between 236 U(gsb) and 238 U(gsb) at low frequencies hω≤ 0.20 MeV are also reproduced quite well.
文摘A comprehensive analysis of the superdeformed bands observed near A≈190 indicates that there exist systematic odd-even differences in the moments of inertia similar to that observed in normally deformed nuclei, which can be considered as compelling evidence for pairing and blocking effect in super-deformed nudei. With increasing rotational frequency the odd-even differences become weaker and weaker due to the Coriolis anti-pairing effects. Particularly, the odd-even differences in the dynamic moments of inertia become obscure when hω≥2 MeV, and in certain cases there emerges nearly identical value of J(2) for some neighboring nudei. However, the odd-even differences in the kinematic moments of inertia still remain to certain extent at the highest frequencies.
文摘The difference in the bandhead moments of inertia between the superdeformed (SD) band 194Hg(1) and the two-quasiparticle SD bands 194Hg(2,3) was investigated using the particle-number-conserving treatment for the cranked shell model Hamiltonian, and the pairing interaction strength in SD nuclei is estimated to be much weaker than that in normally deformed nuclei.
文摘In the particle-number-conserving treatment of the cranked shell model Hamiltonian (blocking effect being taken into account exactly), the calculated even-odd differences in moments of inertia show large variation and depend sensitively on the location and Coriolis response of the blocked levels. The moments of inertia of the 170Yb, 171Lu [404] 7/2, [402] 5/2, [514] 9/2 and 171Yb [512] 5/2, [633] 7/2 bands at low spin are calculated and the experimental data are reproduced very well. No free parameter was involved in the calculation. The reason of the discrepancy between the observed "identical bands" at low spin and the BCS prediction is discussed.