arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2409.04620nucl-thnucl-ex
收藏

超重核中的弱衰变

Weak decays in superheavy nuclei

A. Ravlić, W. Nazarewicz

AI总结:

该研究采用相对论核密度泛函理论与优化相互作用的准粒子无规相位近似,系统计算Z=101–118核的EC/β±衰变,发现一级禁戒1⁻跃迁普遍主导,并识别44个具有可观弱衰变分支的核。

摘要:

超重核代表了处于质量和电荷极限的已知最重原子与核素。观测到的超重核均为丰质子核;它们主要通过发射α粒子和裂变衰变,并可能存在较小的电子俘获(EC)分支。由于巨大的原子序数及相关相对论效应,超重体系的EC衰变预计不同于在较轻核中已知的情况。本文中,我们利用定量化的相对论核密度泛函理论,以及采用针对实验β⁻衰变半衰期和Gamow-Teller共振能量优化的相互作用的准粒子无规相位近似,研究Z=101–118核中的EC/β±衰变。允许跃迁(1⁺)和一级禁戒跃迁(0⁻、1⁻和2⁻)均被考虑。我们表明,一级禁戒1⁻跃迁在几乎所有所研究核中主导衰变率。对于丰质子核,EC相对于β⁺衰变占优。我们识别出44个EC/β⁺分支比大于5%的核,表明其可能与α衰变和自发裂变通道形成竞争。

英文摘要:

Superheavy nuclei represent the heaviest atoms and nuclides known at the limit of mass and charge. The observed superheavy nuclei are all proton-rich; they decay primarily by emitting $α$ particles and fission, with a possible small electron capture (EC) branch. Due to the huge atomic numbers and associated relativistic effects, EC-decays of superheavy systems are expected to differ from what is known in lighter nuclei. In this paper, using the quantified relativistic nuclear density functional theory and the quasiparticle random-phase approximation with the interaction optimized to experimental $β^-$-decay half-lives and Gamow-Teller resonance energies, we study the EC/$β^\pm$-decays in $Z = 101-118$ nuclei. Both allowed ($1^+$) and first-forbidden ($0^-, 1^-$ and $2^-$) transitions are considered. We show that the first-forbidden $1^-$ transitions dominate the decay rates in almost all studied nuclei. For proton-rich nuclei, EC dominates over $β^+$ decay. We identify 44 nuclei with EC/$β^+$ branching ratio larger than 5\%, indicating a possible competition with $α$-decay and spontaneous fission channels.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑