arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 0912.2763nucl-th
收藏

$χ$ EFT框架中的电磁过程

Electromagnetic processes in a $χ$EFT framework

L. Girlanda, S. Pastore, R. Schiavilla, M. Viviani

摘要:

最近,我们在手征有效场论中导出了以π介子和核子为显式自由度的双核子势和一致的核电磁流。电流的计算已进行,包括N $^3$ LO校正,包括两个-π交换和接触的贡献。后者涉及未知的低能常数(LEC),其中一些已被固定的拟合$np$ S-和P-波相移高达100兆电子伏的实验室能量。确定进入当前算子的剩余LEC,以便再现实验氘核和三核子磁矩以及$np$截面。利用该电磁流算符研究了热中子能量下的$nd$和$n^3$ He辐射俘获。在这里,我们讨论我们的结果强调的重要作用,由LEC在再现实验数据。

英文摘要:

Recently, we have derived a two--nucleon potential and consistent nuclear electromagnetic currents in chiral effective field theory with pions and nucleons as explicit degrees of freedom. The calculation of the currents has been carried out to include N$^3$LO corrections, consisting of two--pion exchange and contact contributions. The latter involve unknown low-energy constants (LECs), some of which have been fixed by fitting the $np$ S- and P-wave phase shifts up to 100 MeV lab energies. The remaining LECs entering the current operator are determined so as to reproduce the experimental deuteron and trinucleon magnetic moments, as well as the $np$ cross section. This electromagnetic current operator is utilized to study the $nd$ and $n^3$He radiative captures at thermal neutron energies. Here we discuss our results stressing on the important role played by the LECs in reproducing the experimental data.

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。

↑