Pion form factor phase, ππ elasticity and new e+e− data
نویسندگان
چکیده
منابع مشابه
Ππ Scattering and Pion Form Factors
The S and P wave ππ phase shifts are recalculated in terms of two phenomenological parameters using the one loop CPTh and the elastic unitarity condition. Using these phase shifts, the vector and scalar form factors are calculated and shown to be in a good agreement with experimental data. It is found that the simpler and more phenomenological approach, where the left hand cut contributions to ...
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We re-investigate the impact of isospin violation for extracting the s-wave ππ scattering phase shift difference δ 0 (M K) − δ 2 (M K) from K → ππ decays. Compared to our previous analysis in 2003, more precise experimental data and improved knowledge of low-energy constants are used. In addition, we employ a more robust data-driven method to obtain the phase shift difference δ 0
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The pion, and specifically its charge form factor, is of key interest in the study of the quark-gluon structure of hadrons. This is exemplified by the many calculations that treat the pion as one of their prime examples. One of the reasons is that the valence structure of the pion, being 〈qq̄〉, is relatively simple. Hence it is expected that the value of the four-momentum transfer squared Q, dow...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 2004
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2003.12.030