质子-质子碰撞中 Lambda 和 Sigma^0 超子的产生
核实验
2012-08-27 v1
摘要
本文报告了在超出阈能 204、239 和 284 MeV（Lambda）以及 127、162 和 207 MeV（Sigma^0）下，同时测量反应通道 pp -> pK+Lambda 和 pp -> pK+Sigma^0 的结果。给出了这两个反应的总截面和微分截面。从测量的总截面可以得出结论，截面比的高能极限在仅约 200 MeV 的超出阈能下就已基本达到。从在总体质心系以及 Jackson 参考系和螺旋度参考系中观察到的微分分布得出结论：干涉核子共振对 Lambda 产生机制有显著贡献，而共振 Sigma^0 产生似乎重要性较低，并且仅通过入射通道的特定分波进行。数据还表明，K 介子交换在 Lambda 产生中作用较小，但在 Sigma^0 产生中起重要作用。因此，Lambda 与 Sigma^0 截面比的奇特能量依赖性以一种新的视角呈现，因为其解释需要的不仅仅是 pLambda 和 pSigma^0 末态相互作用之间的差异。这些数据为已有或未来的理论模型提供了基准。
引用
@article{arxiv.1008.4287,
title = {Production of Lambda and Sigma^0 hyperons in proton-proton collisions},
author = {TOF Collaboration and M. Abdel-Bary and S. Abdel-Samad and K-Th. Brinkmann and H. Clement and J. Dietrich and E. Doroshkevich and S. Dshemuchadse and K. Ehrhardt and A. Erhardt and W. Eyrich and D. Filges and A. Filippi and H. Freiesleben and M. Fritsch and W. Gast and J. Georgi and A. Gillitzer and J. Gottwald and D. Hesselbarth and H. Jäger and B. Jakob and R. Jäkel and L. Karsch and K. Kilian and H. Koch and M. Krapp and J. Kreß and E. Kuhlmann and A. Lehmann and S. Marcello and S. Marwinski and S. Mauro and W. Meyer and P. Michel and K. Möller and H. P. Morsch and H. Mörtel and L. Naumann and N. Paul and L. Pinna and C. Pizzolotto and Ch. Plettner and S. Reimann and M. Richter and J. Ritman and E. Roderburg and A. Schamlott and P. Schönmeier and W. Schroeder and M. Schulte-Wissermann and T. Sefzick and F. Stinzig and M. Steinke and G. Y. Sun and A. Teufel and W. Ullrich and G. J. Wagner and M. Wagner and R. Wenzel and A. Wilms and P. Wintz and S. Wirth and P. Wüstner and P. Zupranski},
journal= {arXiv preprint arXiv:1008.4287},
year = {2012}
}
备注
18 pages, 10 figures; accepted by The European Physical Journal A (EPJ A)