用线偏振光子使氘核中束缚的中子单个产生。

Single production off neutrons bound in deuteron with linearly polarized photons.

作者信息

Mullen C, Gardner S, Glazier D I, Kay S J D, Livingston K, Strakovsky I I, Workman R L, Abt S, Achenbach P, Afzal F, Ahmed Z, Akondi C S, Annand J R M, Bashkanov M, Beck R, Biroth M, Borisov N S, Braghieri A, Briscoe W J, Cividini F, Collicott C, Costanza S, Denig A, Dieterle M, Downie E J, Drexler P, Fegan S, Ferretti-Bondy M I, Ghosal D, Gorodnov I, Gradl W, Günther M, Gurevic G, Heijkenskjöld L, Hornidge D, Huber G M, Jermann N, Kaeser A, Korolija M, Kashevarov V L, Krusche B, Kulikov V V, Lazarev A, Lutterer S, MacGregor I J D, Manley D M, Martel P P, Martemianov M A, Meier C, Miskimen R, Mocanu M, Mornacchi E, Neganov A, Oberle M, Ostrick M, Otte P, Paudyal D, Pedroni P, Powell A, Prakhov S N, Reicherz G, Ron G, Rostomyan T, Sfienti C, Sokhoyan V, Spieker K, Steffen O, Strub Th, Supek I, Thiel A, Thiel M, Thomas A, Unverzagt M, Usov Yu A, Wagner S, Walford N K, Watts D P, Werthmüller D, Wettig J, Witthauer L, Wolfes M, Zachariou N

机构信息

SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ UK.

SUPA, School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD UK.

出版信息

Eur Phys J A Hadron Nucl. 2021;57(6):205. doi: 10.1140/epja/s10050-021-00521-9. Epub 2021 Jun 26.

DOI:10.1140/epja/s10050-021-00521-9

PMID:34720708

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8550430/

Abstract

The quasifree photon beam asymmetry, , has been measured at photon energies, , from 390 to 610 MeV, corresponding to center of mass energy from 1.271 to 1.424 GeV, for the first time. The data were collected in the A2 hall of the MAMI electron beam facility with the Crystal Ball and TAPS calorimeters covering pion center-of-mass angles from 49 to 148 . In this kinematic region, polarization observables are sensitive to contributions from the and (1440) resonances. The extracted values of have been compared to predictions based on partial-wave analyses (PWAs) of the existing pion photoproduction database. Our comparison includes the SAID, MAID and Bonn-Gatchina analyses; while a revised SAID fit, including the new measurements, has also been performed. In addition, isospin symmetry is examined as a way to predict photoproduction observables, based on fits to published data in the channels , and .

摘要

首次在390至610 MeV的光子能量（对应质心能量从1.271至1.424 GeV）下测量了准自由光子束不对称性。数据是在MAMI电子束设施的A2大厅收集的，使用了Crystal Ball和TAPS量热计，覆盖了π介子质心角从49 至148 的范围。在这个运动学区域，极化可观测量对和（1440）共振的贡献很敏感。提取的值已与基于现有π介子光生数据库的分波分析（PWA）的预测进行了比较。我们的比较包括SAID、MAID和波恩 - 加奇纳分析；同时还进行了包括新测量的修订后的SAID拟合。此外，基于对、和通道已发表数据的拟合，研究了同位旋对称性作为预测光生可观测量的一种方法。