UNITARITY CUSP IN PROTON COMPTON-SCATTERING

被引：10

作者：

BERGSTROM, JC

HALLIN, EL

机构：

[1] Saskatchewan Accelerator Laboratory, University of Saskatchewan, Saskatoon

来源：

PHYSICAL REVIEW C | 1993年 / 48卷 / 04期

关键词：

D O I：

10.1103/PhysRevC.48.1508

中图分类号：

O57 [原子核物理学、高能物理学];

学科分类号：

070202 ;

摘要：

Recent proton Compton scattering data from Saskatoon spanning the pion threshold region are shown to reflect the presence of a unitarity cusp (Wiper cusp), long predicted but never before observed. The analysis is based on a formulation of the Compton cross section employing convenient semiphenomenological expressions for the four dominant multipole amplitudes, designed to respect the low energy theorem and other constraints. Unitarity anomalies have now been detected in both the elastic (Compton) and inelastic (pi0p) channels of the gamma + p reaction.

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页码：1508 / 1517

页数：10

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