通过双极化测量重新审视已确立的核子共振态
核实验
2015-06-05 v2
摘要
本文报告了中性π介子在质子光致产生过程中双极化可观测量G的首次测量结果，覆盖光子能量范围620至1120 MeV及全立体角。G描述了沿入射光子方向极化的质子的光子极化平面与散射平面之间的关联。该可观测量对重子共振态的贡献高度敏感。新结果与SAID、MAID和BnGa分波分析的理论预测进行了比较。尽管长期以来致力于理解{\gamma}p -> p{\pi} 0这一最简单的光致产生反应，但令人惊讶的是，新数据与最新预测之间存在巨大差异，这些差异归因于自旋 - 宇称J^P = 1/2^-的N(1535)和J^P = 3/2^-的N(1520)贡献的不同。在N(1680)（J^P = 5/2^+）产生占主导的第三共振区，新数据与预测值相当接近。
引用
@article{arxiv.1207.2686,
title = {Well-established nucleon resonances revisited by double-polarization measurements},
author = {A. Thiel and A. V. Anisovich and D. Bayadilov and B. Bantes and R. Beck and Yu. Beloglazov and M. Bichow and S. Böse and K. -Th. Brinkmann and Th. Challand and V. Crede and F. Dietz and P. Drexler and H. Dutz and H. Eberhardt and D. Elsner and R. Ewald and K. Fornet-Ponse and St. Friedrich and F. Frommberger and Ch. Funke and M. Gottschall and M. Grüner and E. Gutz and Ch. Hammann and J. Hannappel and J. Hartmann and W. Hillert and Ph. Hoffmeister and Ch. Honisch and I. Jaegle and I. Jürgensen and D. Kaiser and H. Kalinowsky and F. Kalischewski and S. Kammer and I. Keshelashvili and V. Kleber and F. Klein and E. Klempt and B. Krusche and M. Lang and I. Lopatin and Y. Maghrbi and K. Makonyi and V. Metag and W. Meyer and J. Müller and M. Nanova and V. Nikonov and R. Novotny and D. Piontek and G. Reicherz and A. Sarantsev and Ch. Schmidt and H. Schmieden and T. Seifen and V. Sokhoyan and V. Sumachev and U. Thoma and H. van Pee and D. Walther and Ch. Wendel and U. Wiedner and A. Wilson and A. Winnebeck and Y. Wunderlich},
journal= {arXiv preprint arXiv:1207.2686},
year = {2015}
}
备注
Submitted for publication in PRL