arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0912.0190hep-ph
收藏

排他性$pp \to pp π^{+}π^{-}$反应：从阈值到LHC

Exclusive $pp \to pp π^{+}π^{-}$ reaction: from the threshold to LHC

Piotr Lebiedowicz, Antoni Szczurek

备注：
19 pages, 18 figures
发表信息：
Phys.Rev.D81:036003,2010
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

我们评估差分分布的四体$p p \to p p π^+ π^-$反应构成了一个不可约的背景，三体过程$p p \to p p M$，其中$M$是一个广泛的共振在$π^+ π^-$通道，例如$M=σ, ρ^{0}, f_{0}(980), f_{2}(1275), f_{0}(1500)$。我们包括双衍射的贡献（包括坡密子和reggeon交换），以及π介子-π介子再散射的贡献。第一个过程占主导地位，在较高的能量和小的π-π不变质量，而第二个变得重要，在较低的能量和较高的π-π不变质量。在Regge方法中计算振幅。我们比较我们的结果与测量的截面的ISR实验在欧洲核子研究中心。我们预测未来的实验在PANDA，RHIC，Tevatron和LHC能源。给出了π介子有效质量、π介子快度和横动量的微分分布。$(y_{π^+}, y_{π^-})$中的二维分布特别有趣。入射能量越高，π介子在同一半球发射的优先性越高。所考虑的过程对核子-核子总截面和π介子包含的截面有相当大的贡献。

英文摘要：

We evaluate differential distributions for the four-body $p p \to p p π^+ π^-$ reaction which constitutes a irreducible background to three-body processes $p p \to p p M$, where $M$ are a broad resonances in the $π^+ π^-$ channel, e.g. $M=σ, ρ^{0}, f_{0}(980), f_{2}(1275), f_{0}(1500)$. We include both double-diffractive contribution (both pomeron and reggeon exchanges) as well as the pion-pion rescattering contribution. The first process dominates at higher energies and small pion-pion invariant masses while the second becomes important at lower energies and higher pion-pion invariant masses. The amplitude(s) is(are) calculated in the Regge approach. We compare our results with measured cross sections for the ISR experiments at CERN. We make predictions for future experiments at PANDA, RHIC, Tevatron and LHC energies. Differential distributions in effective two-pion mass, pion rapidities and transverse momenta of pions are presented. The two-dimensional distribution in $(y_{π^+}, y_{π^-})$ is particularly interesting. The higher the incident energy, the higher preference for the same-hemisphere emission of pions. The processes considered constitute a sizeable contribution to the total nucleon-nucleon cross section as well as to pion inclusive cross section.

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。

↑