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arXiv 0911.0634nucl-th
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核束缚的奇偶交错与液滴模型

Odd-even staggering in nuclear binding and the liquid-drop model

W. A. Friedman

摘要:

本文用常规方法$Δ^{(3)}$研究了中子和质子核束缚的奇偶交错效应随质量数的变化趋势。先前观察到的这些措施的偶数和奇数值的趋势之间的巨大差异被发现出现,部分地,从结合能与质量和电荷的缓慢变化,提供了一个背景贡献。这个背景估计与液滴模型,并占质子去除相对于中子去除中发现的更大的差异。去除背景后仍然存在的差异不能用传统的液滴模型来处理,而需要增加一个新的项。研究了这一项,并计算了它对OES具体值的影响。液滴拟合也适用于一组分离能约束,以匹配用于确定奇数$Δ^{(3)}$的观测值的特定的一组核。将配对项的拟合结果与偶数和奇数测量的平均值进行比较。观察到新的液滴项对该值的影响,并且当包括新的项时背景中的变化也被用作用于确定OES的偶数值和奇数值的趋势之间的差异的替代方法。

英文摘要:

The trends with mass number are examined for the odd-even-staggering (OES) in nuclear binding of neutrons and protons through the conventional measures $Δ^{(3)}$. The large differences previously observed between these trends for even and odd values of these measures is found to arise, in part, from the slow variation of binding energies with mass and charge which provides a background contribution. This background is estimated with the liquid-drop model, and accounts for the greater difference found in proton removal relative to neutron removal. The differences which persist after backgrounds are removed can not be treated in the conventional liquid-drop model but require the addition of a new term. Such a term is investigated, and its effect on specific values of the OES is calcutated. The liquid-drop fitting is also applied to a set of separation energies constrained to match the specific set of nuclei used to determine the observed values for the odd $Δ^{(3)}$. The resulting fit for the pairing term is compared to the average value of even and odd measures. The effect on this value of the new liquid-drop term is observed, and the change in background when the new term is included is also used as an alternate method for determining the difference between trends of the even and odd values of the OES.

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。

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