arXiv 2003.061752020-03-13nucl-th

由双核子势参数的不确定性引起的三核子连续谱观测量的不确定性

Uncertainty of three-nucleon continuum observables arising from uncertainties of two-nucleon potential parameters

Yu. Volkotrub, J. Golak, R. Skibiński, K. Topolnicki, H. Witała, E. Epelbaum, H. Krebs, P. Reinert

备注：: 18 pages, 14 figures in 29 eps files

摘要：

本文研究了在中子实验室能量达200 MeV的情况下，中子-氘弹性散射和氘破裂反应的不确定性从两核子势参数到三核子可观测量的传播，即统计误差。为此，我们使用的手征核子相互作用的半局部动量空间正则化在各种订单的手征展开，利用知识的协方差矩阵的参数。对于这两个反应，我们比较统计的不确定性手性预测的不确定性，但以同样的方式获得的半唯象单π交换两核子力。此外，对于弹性散射，我们还显示了截断误差所产生的限制，以一个给定的顺序的手性预测，估计在其他贝叶斯方法，和截断依赖的手性预测。我们发现，由此产生的统计不确定性是小于截断误差的手征力在较低的手征展开。在高阶手征展开和低能时，统计误差超过截断误差，但在中高能时截断误差更为重要。总的来说，理论不确定度的大小很小，根据可观测量和能量的不同，不确定度可达0.5%~ 4%。我们还发现，统计不确定性的手征和半唯象势的大小是相似的，预测的正则化参数值的依赖性是很重要的，在所有调查的能量。

英文摘要：

Propagation of uncertainties from two-nucleon potential parameters to three-nucleon observables, that is statistical errors for the neutron-deuteron elastic scattering and the deuteron breakup reaction at neutron laboratory energies up to 200 MeV is investigated. To that end we use the chiral nucleon-nucleon interaction with the semi-local momentum-space regularization at various orders of the chiral expansion, exploiting knowledge of the covariance matrix of its parameters. For both reactions we compare statistical uncertainties for chiral predictions with the uncertainties obtained in the same way but for the semi-phenomenological One-Pion-Exchange two-nucleon force. In addition for the elastic scattering we show also the truncation errors arising from restriction to a given order of chiral predictions, estimated among others within the Bayesian method, and the cutoff dependence of chiral predictions. We find that the resulting statistical uncertainty is smaller than the truncation errors for the chiral force at lower orders of the chiral expansion. At the higher orders of the chiral expansion and at low energies the statistical errors exceed the truncation ones but at intermediate and higher energies truncation errors are more important. Overall, magnitudes of the theoretical uncertainties are small and amount up to 0.5\%-4\%, depending on the observable and energy. We also find that the magnitudes of statistical uncertainties for the chiral and semi-phenomenological potentials are similar and that the dependence of predictions on the regularization parameter values is important at all investigated energies.

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。

摘要：

英文摘要：

相关论文