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arXiv 1701.08211nucl-th
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具有双核子和三核子短程关联的有限核的微观核子谱函数:I。三核子体系的模型与从头计算

A microscopic nucleon spectral function for finite nuclei featuring two- and trhee-nucleon short-range correlations: I. The model vs. ab-initio calculations for the three-nucleon systems

Claudio Ciofi degli Atti, Chiara Benedetta Mezzetti, Hiko Morita

摘要:

本文介绍了在两核子(2N)和三核子(3 N)短程关联(SRC)范围内描述单核子动量分布n(k_1)和谱函数P(k_1)的卷积模型的主要特点,E)根据涉及相对n_{rel}的卷积积分详细说明了核子-核子对的质心动量分布(k_{rel})和质心动量分布(n_{c.m.}(K_{c.m.}))。它强调,该模型,它源于在短的核子间距离的核波函数所表现出的因式分解的普适属性,是只适用于一个明确定义的区域的k_{rel}和K_{c.m.},它示出,特别是,因式分解的要求引入了严格的约束值的k_{rel}和K_{c.m.}出现在卷积积分。使用从头算相对论和c.m.通过计算^3He的动量分布,将卷积模型的谱函数和动量分布与用真实的Argonne族局域NN相互作用进行的从头计算结果进行比较,研究了卷积模型的有效性。结果表明,当正确考虑对k_{rel}和K_{c.m.}的值的约束,仅考虑2N SRC时,卷积模型在后者所显示的峰区域与从头算谱函数吻合得很好,而远离峰,特别是在高去除能值时,只有考虑3 N SRC的影响,模型谱函数才能定性地与从头算谱函数一致。至于核子动量分布,3 N SRC的影响似乎很小。

英文摘要:

The main features of the convolution model which, in the region of two-nucleon (2N) and three-nucleon (3N) short-range correlations (SRC), describes the one-nucleon momentum distribution n(k_1) and the spectral function P(k_1,E) in terms of a convolution integral involving the relative n_{rel}(k_{rel}) and the center-of-mass n_{c.m.}(K_{c.m.}) momentum distributions of a nucleon-nucleon pair, are illustrated in detail. It is stressed that the model, which stems from the universal property of factorization exhibited by the nuclear wave function at short inter-nucleon distances, is only applicable in a well-defined region of k_{rel} and K_{c.m.}; it is shown, in particular, that the requirement of factorization introduces a severe constraint on the values of k_{rel} and K_{c.m.} that appear in the convolution integral. Using ab-initio relative and c.m. momentum distributions for ^3He, the validity of the convolution model is investigated by comparing the model spectral function and momentum distributions with the ones resulting from ab-initio calculations performed with realistic local NN interaction of the Argonne family. It is shown that when the constraint on the value of k_{rel} and K_{c.m.} are correctly taken into account and only 2N SRC are taken into account, the convolution model is in good agreement with the ab-initio spectral function in the region of the peak exhibited by the latter, whereas far from the peak, particularly at high values of the removal energy, the model spectral function can be qualitatively reconciled with the ab-initio spectral function only by considering the effects of 3N SRC. As for the nucleon momentum distribution, the effects of 3N SRC appears to be very small.

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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