An extensive study on the search of stable isotopes for Z = 119 and121 superheavy nuclei is performed within relativistic mean field model with NL3 force for axially deformed nuclei. Our search is accomplished in the mass region,289 ≤ A ≤ 339. The ground state properties such as binding energy, quadrupole deformation, root-mean square radius etc. are calculated and compared with finite range droplet model (FRDM). Calculated results are found to be in good agreement with FRDM results. The stability of superheavy isotopes against all the elementary decay modes (α-decay, β-decay and spontaneous fission process) are studied. The most stable isotopes are chosen by scrutinizing their various nuclear properties. For Z = 119, the stable isotopes are found to be ^{291, 292}119, ^{294−298}119 and for Z = 121, only isotope ^{297}121 found to be relatively more stable in their considered isotopic chain. The predicted stable isotopes in the superheavy region along their isotopic chain, are found near the proton drip line. Further, the single particle spectrum and deform density profile along different direction are shown for few predicted stable isotopes, to gather a sound knowledge on the their features.

中文翻译：

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使用相对论平均场模型搜索 Z = 119 和 121 超重元素的稳定同位素

对 Z = 119 和 121 超重核的稳定同位素搜索的广泛研究是在相对论平均场模型中使用 NL3 力对轴向变形核进行的。我们的搜索是在质量区域完成的，289 ≤ A ≤ 339。计算基态特性，如结合能、四极变形、均方根半径等，并与有限范围液滴模型（FRDM）进行比较。发现计算结果与 FRDM 结果非常一致。研究了超重同位素对所有基本衰变模式（α-衰变、β-衰变和自发裂变过程）的稳定性。最稳定的同位素是通过仔细检查它们的各种核特性来选择的。对于 Z = 119，发现稳定同位素为 ^{291, 292}119, ^{294−298}119，对于 Z = 121，只有同位素 ^{297}121 在他们考虑的同位素链中相对更稳定。在质子滴线附近发现了沿其同位素链的超重区域中预测的稳定同位素。此外，针对少数预测的稳定同位素显示了沿不同方向的单粒子谱和变形密度剖面，以收集有关其特征的可靠知识。