Threshold $$\pi ^-$$ π - photoproduction on the neutron
The European Physical Journal A(2020)
摘要
Recent data from the PIONS@MAX-lab Collaboration, measuring the total cross section of the incoherent pion photoproduction reaction,
$$\gamma d\rightarrow \pi ^- pp$$
, near threshold, have been used to extract the
$$E_{0+}$$
multipole and total cross section of the reaction
$$\gamma n\rightarrow \pi ^-p$$
, also near threshold. These are the first measurements of the reaction
$$\gamma d\rightarrow \pi ^- pp$$
in the threshold region. The value of
$$E_{0+}$$
is extracted through a fit to the deuteron data in a photoproduction model accounting for final-state interactions. The model takes an S-wave approximation for the elementary reaction
$$\gamma n\rightarrow \pi ^-p$$
with
$$\hbox {E}_{0+} = $$
const in the threshold region. The fit over all the 6 deuteron data points gives the value
$$E_{0+} = -\,31.86\pm 0.8$$
(in units
$$10^{-3}/m_\pi $$
). We explore the dependence of our results on the choice of data subsets included in the fit. The obtained values of
$$E_{0+}$$
, for different subsets, have overlapping errors and agree with previous determinations.
更多查看译文
关键词
neutron,threshold,$$\pi
AI 理解论文
溯源树
样例
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要