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11.
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A.M. El-Badry T. Kuroyanagi S. Mitarai A. Odahara Y. Gono S. Morinobu K. Ogawa 《The European Physical Journal A - Hadrons and Nuclei》1998,3(2):133-138
A recoil distance method was used to measure half-lives of the excited states of 145Sm. The reaction used was 139La(10B, 4n)145Sm. A plunger system was used. Half-lives were determined for two excited states for the first time. The yrast 27/2+ state was found to have a half-life of 1.1 ± 0.2 ns corresponding to the retardation of 3.1 × 10−4 comparing with the single particle estimate of M1. The excitation energy of this state was well reproduced by the shell model
calculation having a mixed configuration of [π{h11/2(g7/2)−2 (d5/2)−1}10−, νf7/2] + [π{h11/2(g7/2)−1}9−,νh9/2]. Another retarded E1 transition was also found in a decay of a 21/2+ state. Its retardation was 1.6 × 10−4 comparing with the single particle value.
Received: 9 September 1997 / Revised version: 12 June 1998 相似文献
13.
Y.K. Gambhir J.P. Maharana C.S. Warke 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):255-262
The existence of broken pseudo-spin symmetry in the Pb nucleus has been studied in the relativistic mean field approach using
realistic Lagrangian parameters. Its relationship to spin orbit splitting and the vanishingly small surface delta character
of the mean spin orbit potential are investigated. In the 208Pb nucleus the broken pseudo-spin doublets are found to exist above the neutron (proton) Fermi surfaces.
Received: 16 April 1998 / Revised version: 26 June 1998 相似文献
14.
T.R. Saitoh N. Hashimoto G. Sletten R.A. Bark S. Törmänen M. Bergström K. Furuno K. Furutaka G.B. Hagemann T. Hayakawa T. Komatsubara A. Maj S. Mitarai M. Oshima J. Sampson T. Shizuma P.G. Varmette 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):197-199
High-spin states in 181Ta have been studied via the 176Yb(11B,α2n) reaction at 52 MeV using the PEX array and at 57 MeV using the NORDBALL array, with α-particle detection. The previously
known, Kπ=(7/2)+ ground state band and Kπ=(9/2)− band have been extended to spins (29/2)+ and (31/2)−, respectively. Two new one-quasiparticle bands, the Kπ=(5/2)+ band built on the known (5/2)+ isomer and a Kπ=((1/2)−) band have been observed. Two other rotational bands with three-quasiparticle structure, Kπ=(15/2)− and ((19/2)+ with π(7/2)[404]ν2(1/2)[510](9/2)[624] and π(9/2)[514]ν2(1/2)[510](9/2)[624] configurations, respectively, have been newly observed. The half-life of the Kπ=((19/2)+) bandhead which decays to the head of the (15/2)− band has been measured to be 140(36) ns. However, transitions from the ((19/2)+) state to the (15/2)− band have not been observed.
Received: 26 August 1998 相似文献
15.
Single crystals of U3+:LaBr3 were grown by the Bridgman-Stockbarger technique. High-resolution polarized absorption spectra of the crystals were recorded at 4.2 K in the 4000-50,000 cm−1 range. Sixty-four experimental crystal-field energy levels of the U3+ ion were fitted to a semiempirical Hamiltonian employing free-ion, one-electron crystal-field as well as two-particle correlation crystal-field (CCF) operators with an r.m.s. deviation of 28 cm−1. The performed analysis of the spectra enabled the determination of crystal-field parameters and assignment of the observed 5f3→5f3 transitions. The effects of selected CCF operators on the splitting of some specific U3+ multiplets have been investigated and the obtained values of Hamiltonian parameters are discussed and compared with those reported in previous analyses. 相似文献
16.
Purely vibrational energy levels and partition functions are calculated using three different potential energy surfaces for the H2O molecule. Results obtained with perturbation-theory, independent-normal-mode (INM), and harmonic approximations are compared with accurate values. For the cases considered here, the expected improvement that perturbation theory provides over the corresponding harmonic treatment is found to be substantial, while the INM approximation leads to results which are worse than the corresponding harmonic ones. In fact, we show that reliable partition functions for these potential surfaces can be obtained when resonance contributions are removed from the perturbation-theory treatment, and we propose a theoretical criterion for deciding when a particular interaction should be treated as resonant. 相似文献
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为了突破传统测温技术应用的局限性,利用NaY (WO4)2:Eu3+玻璃陶瓷(glass ceramics,GC)实现了具有非接触、实时响应、自校准等优势的双模荧光强度比(luminescence intensity ratio,LIR)测温。采用高温熔融淬灭法制备出含NaY (WO4)2:Eu3+纳米晶的透明GC样品,并进行系列光谱测量和热敏性能分析。结果表明,样品中Eu3+的激发态能级5D1和5D0和基态能级7F2和7F0为两对独立的热耦合能级,可分别基于这两对热耦合能级实现性能优异的双模LIR温度传感。该双模LIR测温技术数据可靠、测温范围广、灵敏度高,再结合GC材料优势,是可用于光纤温度传感器的核心技术材料。 相似文献
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本文试图以浅显明确的形式描述对称轴定理,使之能与对称面定理相媲美,并对对称轴定理作一定的扩展,给出分子轨道构造定理。 相似文献