Study of the N = 32 and N = 34 Shell Gap for Ti and V by the First High-Precision Multireflection Time-of-Flight Mass Measurements at BigRIPS-SLOWRI
Study of the N = 32 and N = 34 Shell Gap for Ti and V by the First High-Precision Multireflection Time-of-Flight Mass Measurements at BigRIPS-SLOWRI
复制标题
通过 BigRIPS-SLOWRI 首次高精度多重反射飞行时间质量测量研究 Ti 和 V 的 N = 32 和 N = 34 壳间隙
DOI：
10.1103/physrevlett.130.012501
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发表时间：
2023
影响因子：
8.6
通讯作者：
Ni
中科院分区：
文献类型：
--
作者：
Iimura S.;Rosenbusch M.;Takamine A.;Tsunoda Y.;Wada M.;Chen S.;Hou D.S.;Xian W.;Ishiyama H.;Yan S.;Schury P.;Crawford H.;Doornenbal P.;Hirayama Y.;Ito Y.;Kimura S.;Koiwai T.;Kojima T.M.;Koura H.;Lee J.;Liu J.;Michimasa S.;Miyatake H.;Moon J.Y.;Naimi S.;Ni
的原子质量，和已确定使用高精度的多重反射飞行时间技术。放射性同位素在RIKEN的放射性同位素束工厂（RIBF）生产，并交付给新设计的气室和多重反射系统，该系统最近在BigRIPS分离器之后的ZeroDegree光谱仪下游投入使用。对于和，质量的不确定性已降低到10 keV的数量级，通过对临界物质和的首次高精度质量测量，对Ti和V同位素的壳效应提供了新的认识。在新的精度下，我们揭示了Ti和V的经验双中子壳能隙的不存在，而在占据轨道之上的增强能隙被认为是Ca所独有的特征。我们进行了新的蒙特卡罗壳模型计算，包括和轨道，并将结果与传统的壳模型计算，其中不包括和轨道。比较结果表明，Ti的壳层间隙减小与外层两价中子在高轨道上的部分占据有关。
The atomic masses of,, andhave been determined using the high-precision multireflection time-of-flight technique. The radioisotopes have been produced at RIKEN’s Radioactive Isotope Beam Factory (RIBF) and delivered to the novel designed gas cell and multireflection system, which has been recently commissioned downstream of the ZeroDegree spectrometer following the BigRIPS separator. Forand, the mass uncertainties have been reduced down to the order of 10 keV, shedding new light on theshell effect in Ti and V isotopes by the first high-precision mass measurements of the critical speciesand. With the new precision achieved, we reveal the nonexistence of theempirical two-neutron shell gaps for Ti and V, and the enhanced energy gap above the occupiedorbit is identified as a feature unique to Ca. We perform new Monte Carlo shell model calculations including theandorbits and compare the results with conventional shell model calculations, which exclude theand theorbits. The comparison indicates that the shell gap reduction in Ti is related to a partial occupation of the higher orbitals for the outer two valence neutrons at.