Nuclear levels in the doubly oddTa182nucleus

Abstract

The low-energy part of the radiation emitted after thermal neutron capture in "'Ta has been investigated by different experimental techniques: Gamma-ray measurements were performed with a diffraction spectrometer, The conversion electron spectrum was recorded with a P spectrograph and measurements of gamma-gamma coincidences were carried out. For ten rotational bands in '"Ta, which were already proposed in an earlier work, a large amount of new decay data has been obtained and for most of these bands higher rotational levels have been found. These ten bands have for their lowest level the following energies and I K values: 0 keV 3 3, 16 keV 5+5, 114 keV 4 4, 150 keV 4+4, 173 keV 5 5, 250 keV 3+3, 270 keV 2 2, 402 keV 2+2, 547 keV 3 3, and 558 keV 1 0. New rotational bands with the following band head energies and structure have been established: 443.6 keV [5/2+[402]r, 3/2 [512]"]a "593. 0 keV [7/2+[404], 9/2+[624]"]a "and 647.6 keV [5/2+[402]", 1/2 [510]"]a z. Tentative band heads have been proposed at 390, 740, and 749 keV with I K values 6+6, 2 2, and 3+3. For the sake of completeness, previously found levels with K values ranging from seven to ten are also discussed. NUCLEAR REACTIONS Ta(n, y), E= thermal; measured Ey s Iy s Igg p pp coincidences. Ta deduced levels J, m, K, cc, p multipolarities, J of Ta neutron resonances. Natural targets.

Signature splitting in two quasiparticle rotational bands of 180,182Ta

“…From the present calculations, we also suggest that the Newby shift energy for the K π = 0 − band under study is −23.6 keV, which is in reasonable agreement with the previously reported value (−26.5 keV) by Jain et al [17] and this Newby shift energy plays a vital role for the explanation of observed signature splitting. From figure 6a, it is clear that there is an excellent agreement between the present TQPRM calculations and the experimental results, which further strengthen the spin, parity and configuration assignment to this band by Cruyce et al [14]. We also extend this band to higher spins (up to 11h) as a future prediction for experimentalists and this extension could be useful to the experimentalists for fixing the level energies at higher spins.…”

“…The K π = 1 + : 7/2[404] π ⊗9/2[624] ν band is also observed in 180 Ta and exhibits the pronounced signature splitting throughout the whole spin range (figure 2a). But in 182 Ta, only band head is confirmed for this band and two higher levels namely 2 − at 647.4 keV and 3 − at 724.0 keV are completely tentative in nature [14]. Hence, it is a good example for the present calculations for prediction of band structure at higher spins.…”

“…(3) To confirm the tentative nature of this band which could not be firmly established in the earlier studies [14,15]. (4) To extend this band up to higher spin levels so that future prediction for the experimentalists could be made.…”

“…The admixture of wave functions taking part in K π = 0 − : 9/2 − [514] π ⊗ 9/2 + [624] ν Coriolis mixing. [14].…”

“…This isomeric state lives more than 1.2×10 15 yr [4,5] which is much large as compared to the K π = 1 + : 7/2 + [404] π ⊗9/2 + [624] ν ground state whose half-life is only 8.18 h [6,7]. During the last few decades the structures of tantalum nuclides, namely 180 Ta and 182 Ta, have been explored by various experimental studies [8][9][10][11][12][13][14][15].…”