Results 1 - 10 of 859
Results 1 - 10 of 859. Search took: 0.02 seconds
|Sort by: date | relevance|
[en] Combining the new spectroscopy results of "1"4"4Tb and previous spectroscopy studies of neighboring nuclei, a systematic investigation on the low-lying spectra in N = 78 ~ 80 isotones is performed. Good systematics have been found for the coupling patterns which couple the odd nucleon(s), such as πh_1_1_/_2, νh_1_1_/_2"—"1, νh_1_1_/_2"2, νh_1_1_/_2"—"2, νh_1_1_/_2"—"1, to the 2"+, 4"+, 6"+ and 3"- core excitations. It is found that the relative excitation energies of the states formed by coupling h_1_1_/_2 proton(s) to the 2"+, 4"+ core excitations are pushed up, in contrast with those formed by coupling h_1_1_/_2 neutron hole(s) to the 2"+, 4"+ core excitations, which are pulled down. According to the systematics, the interpretation that the 17/2"+ states observed in "1"4"1Sm and "1"4"3Gd are the fully aligned member of coupling the odd h_1_1_/_2 neutron hole to the octupole 3"- core excitation, is explored to the isotones "1"4"5Dy, "1"4"2Eu, and "1"4"4Tb. (author)
[en] Magnetic Rotation (MR) band crossing is studied systematically in N=78 isotones (La, Pr, Pm and Eu) using Tilted Axis Cranking (TAC) model. The observables such as I(¯h) vs ¯hω, excitation energy E(MeV) vs spin I(¯h), and the B(M1)/B(E2) vs I(¯h) were considered to pinpoint MR crossing in these nuclei. The results of tilted axis cranking were compared with these experimental observables. The B(M1) and B(E2) values were also reported and used to understand the crossing behaviour of these MR bands. The systematic evolution of this phenomenon in N=78 odd-Z istotones leads to understand the role of nucleons in MR band crossing
[en] The potential energy surfaces of the isotopes of Kr, Rb, Sr and Zr and the isotones in the region of the nuclear landscape display interesting shape variations with N and Z. The shape evolution and the possible shape coexistence are discussed within the cranked Nilsson-Strutinsky (CNS) framework for the isotopic and isotonic chains. The results indicate an oblate shell gap at and 37 and a prolate shell gap at and 40 with deformation . Our calculations show a well deformed prolate shell gap at so that it is determinant in the nuclear shape in this mass region.
[en] With new experimental information on nuclei far from stability being available, a systematic investigation of excitation energies and electromagnetic properties along the N=10,11,12 isotones and Z=10,11,12 isotopes is presented. The experimental data are discussed in the context of the appearance and disappearance of shell closures at N=Z=8,14,16,20, and compared to an effective-interaction approach applied to neutrons and protons in d configurations. In spite of its simplicity the model is able to explain the observed properties.
[en] It has been pointed out that for nuclei rotating around an axis perpendicular to the symmetry axis, Lagrangian multiplier method is not valid. The angular momentum in these nuclei has been generated by tuning the cranking frequency ω in the Nilsson Hamiltonian. In this paper above approach is extended to N=50 isotones in the zirconium region. Here x-axis is chosen as the axis of rotation. Calculations are performed for nuclei Z 36,38,40 and 42. The total energy is minimized with respect to the deformation parameters
[en] A systematic of the experimental values of the average neutron reduced width for the nuclei of the isotonic groups is given. The following remarks can be made: in each isotonic group the values of GAMMAsub(n)sup(0) are systematically higher for the nuclei with Z even and Z odd, for the nuclei with I = 1/2, a dependence of GAMMAsub(n)sup(0) on the spin of resonance is found. (author)
[en] The low-energy level structures for the neutron-rich Co isotopes at N = 39 and N = 41 are constructed following the beta decay of the respective even-even Fe isotopes. Spin and parity assignments of the lowest energy populated state in 66Co and 68Co are consistent with a 1+ spin and parity assignment and attributed to the coupling of the deformed proton configurations identified in 67Co and deformed neutron configurations inferred from neighboring Fe isotones. Comparisons along the N = 39 and N = 41 isotonic chains reveal a similarity in the structures of the Co and Mn isotopes.