利用 MAMI 的 A2 装置测量 omega -> pi^0 e^+e^- 和 eta -> e^+e^-g Dalitz 衰变
高能物理 - 实验
2017-04-26 v2 核实验
摘要
利用 Mainz Microtron (MAMI) 的 A2 标记光子设施，分别在 g p -> eta p 和 g p -> omega p 反应中测量了 Dalitz 衰变 eta -> e^+e^-g 和 omega -> pi^0 e^+e^-。得到的 eta 电磁跃迁形状因子的斜率参数 Lambda^{-2}_eta=(1.97+/-0.11_tot) GeV^{-2} 与先前对 eta -> e^+e^-g 和 eta -> mu^+mu^-g 衰变的测量结果吻合良好。所获得的 Lambda^{-2}_eta 的不确定度低于先前基于 eta -> e^+e^-g 衰变的结果。得到的 omega 斜率参数 Lambda^{-2}_omega_pi^0 = (1.99+/-0.21_tot) GeV^{-2} 略低于先前基于 omega -> pi^0 mu^+mu^- 的测量结果，但与早期实验相比，关于 omega 跃迁形状因子的结果与理论计算更为一致。
引用
@article{arxiv.1609.04503,
title = {Measurement of the omega -> pi^0 e^+e^- and eta -> e^+e^-g Dalitz decays with the A2 setup at MAMI},
author = {P. Adlarson and F. Afzal and P. Aguar-Bartolomé and Z. Ahmed and J. R. M. Annand and H. J. Arends and K. Bantawa and R. Beck and H. Berghäuser and M. Biroth and N. S. Borisov and A. Braghieri and W. J. Briscoe and S. Cherepnya and F. Cividini and C. Collicott and S. Costanza and I. V. Danilkin and A. Denig and M. Dieterle and E. J. Downie and P. Drexler and M. I. Ferretti Bondy and L. V. Fil'kov and S. Gardner and S. Garni and D. I. Glazier and D. Glowa and W. Gradl and G. M. Gurevich and D. J. Hamilton and D. Hornidge and G. M. Huber and T. C. Jude and A. Käser and V. L. Kashevarov and S. Kay and I. Keshelashvili and R. Kondratiev and M. Korolija and B. Krusche and A. Lazarev and J. Linturi and V. Lisin and K. Livingston and I. J. D. MacGregor and R. Macrae and D. M. Manley and P. P. Martel and J. C. McGeorge and E. F. McNicoll and V. Metag and D. G. Middleton and R. Miskimen and E. Mornacchi and C. Mullen and A. Mushkarenkov and A. Neganov and A. Neiser and A. Nikolaev and M. Oberle and M. Ostrick and P. Ott and P. B. Otte and D. Paudyal and P. Pedroni and A. Polonski and S. Prakhov and A. Rajabi and J. Robinson and G. Ron and G. Rosner and T. Rostomyan and C. Sfienti and M. H. Sikora and V. Sokhoyan and K. Spieker and O. Steffen and I. I. Strakovsky and B. Strandberg and Th. Strub and I. Supek and A. Thiel and M. Thiel and A. Thomas and M. Unverzagt and Yu. A. Usov and S. Wagner and N. Walford and D. P. Watts and D. Werthmüller and J. Wettig and L. Witthauer and M. Wolfes and L. A. Zana},
journal= {arXiv preprint arXiv:1609.04503},
year = {2017}
}
备注
19 figures, 2 tables