eta-prime nucleus optical potential and possible eta-prime bound states
eta-prime nucleus optical potential and possible eta-prime bound states
复制标题
eta素核光学势和可能的eta素束缚态
DOI：
10.1016/j.physletb.2012.01.061
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发表时间：
2012
影响因子：
4.4
通讯作者：
et al
中科院分区：
文献类型：
--
作者：
Hideko Nagahiro;et al
从最近的一个η′N相互作用模型出发，我们计算了η′-核光学势，包括密度最低阶的贡献，[公式：见正文]，以及解释两个核子对η′吸收的二阶项。我们还计算了（π+，p）核反应的η′束缚态的形成截面.η′-核势的不确定性与η′-N相互作用的知之甚少有关，这可能部分受到η′-N散射长度的实验模量和/或最近测量的η′-核光生的透明度比的限制。假设存在吸引相互作用，并取实验值[公式：见正文]，我们得到饱和密度为[公式：见正文]的核物质中的η′光学势，其吸引力不足以在轻核中产生η′束缚态。散射长度的值越大，产生的光学势越深，虚部足够适中。对于值[公式：[见正文]，这仍然可以被认为是在实验约束的不确定性之内，轻核和中等核的光谱显示出与η′核束缚态和未束缚区阈值增强相关的清晰结构。
Starting from a recent model of the η′N interaction, we evaluate the η′-nucleus optical potential, including the contribution of lowest order in density, [Formula: see text] , together with the second-order terms accounting for η′absorption by two nucleons. We also calculate the formation cross section of the η′bound states from (π+,p) reactions on nuclei. The η′-nucleus potential suffers from uncertainties tied to the poorly known η′N interaction, which can be partially constrained by the experimental modulus of the η′N scattering length and/or the recently measured transparency ratios in η′nuclear photoproduction. Assuming an attractive interaction and taking the claimed experimental value [Formula: see text] , we obtain an η′optical potential in nuclear matter at saturation density of [Formula: see text] , not attractive enough to produce η′bound states in light nuclei. Larger values of the scattering length give rise to deeper optical potentials, with moderate enough imaginary parts. For a value [Formula: see text] , which can still be considered to lie within the uncertainties of the experimental constraints, the spectra of light and medium nuclei show clear structures associated to η′-nuclear bound states and to threshold enhancements in the unbound region.