Implication of the observed $ψ(3770)\to p\bar{p}π^0$ for studying the $p\bar{p}\to ψ(3770)π^0$ process
Lanzhou University(兰州大学);Institute of Modern Physics, Chinese Academy of Sciences(中国科学院近代物理研究所);School of Physical Science and Technology, Lanzhou University(兰州大学物理科学与技术学院);Institute of Theoretical Physics, Chinese Academy of Sciences(中国科学院理论物理研究所)
Hao Xu, Ju-Jun Xie, Xiang Liu
备注:
8 pages, 10 figures, and 4 tables. Accepted by Eur. Phys. J. C. updated some results according to an erratum
发表信息:
Eur. Phys. J. C 76, 192 (2016);Erratum: Eur. Phys. J. C 86, 1195 (2026)
We study the charmonium $p \bar{p} \to ψ(3770) π^0$ reaction using the effective lagrangian approach where the contributions from well established $N^*$ states are considered, and all parameters are fixed in the process of $e^+e^- \to p \bar{p}π^0$ at center of mass energy $\sqrt{s} = 3.773$ GeV. The experimental data on the line shape of the mass distribution of the $e^+e^- \to p\bar{p}π^0$ can be well reproduced. Based on the studying of $e^+e^- \to p \bar{p}π^0$, the total and differential cross sections of the $p \bar{p} \to ψ(3770) π^0$ reaction are predicted. At the same time we evaluated also the cross sections of the $p \bar{p} \to ψ(3686) π^0$ reaction. It is shown that the contribution of the nucleon pole to this reaction is largest from the reaction threshold within a wide range. However, the interference between nucleon pole and the other nucleon resonance can still change the angle distributions significantly. Those theoretical results may be test by the future experiments at $\overline{\mbox{P}}$ANDA.
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