论文标题
从开创性原子中提取$σ_{πn} $
Extracting $σ_{πN}$ from pionic atoms
论文作者
论文摘要
我们从周期表中的大规模拟合pioninic-atm strontaction数据中讨论了$πn$ $σ$ term $σ_{πn} $的最新提取。因此得出的值，$σ_{πn}^{\ rm fg} = 57 \ pm 7 $ meV，通过gell-mann-oakes-oakes- lenner表达式直接连接到中等肾上腺质量的$πn$ ISOVECTOR散射幅度接近Threshold。它与Bern-Bonn-JülichGroup最近得出的值进行了很好的比较，$σ_{πn}^{\ rm rs rs} = 58 \ pm 5 $ MeV，使用Roy-Steiner方程控制了差不多的小$πn$πn$πn$ iSscalar sceera sceero sceo zero pion to zero pion pion to pion。
We discuss a recent extraction of the $πN$ $σ$ term $σ_{πN}$ from a large-scale fit of pionic-atom strong-interaction data across the periodic table. The value thus derived, $σ_{πN}^{\rm FG}=57\pm 7$ MeV, is directly connected via the Gell-Mann--Oakes--Renner expression to the medium-renormalized $πN$ isovector scattering amplitude near threshold. It compares well with the value derived recently by the Bern-Bonn-Jülich group, $σ_{πN}^{\rm RS}=58\pm 5$ MeV, using the Roy-Steiner equations to control the extrapolation of the vanishingly small near threshold $πN$ isoscalar scattering amplitude to zero pion mass.
