/ 97 04 41 5 v 1 2 8 A pr 1 99 7 Elastic π N Scattering to O ( p 3 ) in Heavy Baryon Chiral Perturbation Theory ∗
نویسنده
چکیده
The elastic πN scattering amplitude in the isospin limit is calculated in the framework of heavy baryon chiral perturbation theory, up to the third order. Threshold parameters like scattering lengths, volumes, effective ranges, etc. are compared with data. All relevant low energy constants are fixed from the available pion-nucleon data. A clear improvement in the description of data is observed, when going from the first two orders in the chiral expansion to the third one. The importance of even higher orders is suggested by the results.
منابع مشابه
5 v 2 2 5 Ju n 19 97 Elastic π N Scattering to O ( p 3 ) in Heavy Baryon Chiral Perturbation Theory ∗
The elastic πN scattering amplitude in the isospin limit is calculated in the framework of heavy baryon chiral perturbation theory, up to the third order. Threshold parameters like scattering lengths, volumes, effective ranges, etc. are compared with data. All relevant low energy constants are fixed from the available pion-nucleon data. A clear improvement in the description of data is observed...
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متن کاملar X iv : h ep - p h / 97 10 46 8 v 1 2 4 O ct 1 99 7 Connections Between Lattice Gauge Theory and Chiral Perturbation Theory
In this talk, I address the comparison between results from lattice QCD computations and Chiral Perturbation Theory (ChPT). I briefly discuss how ChPT can be adapted to the much-used quenched approximation and what it tells us about the special role of the η ′ in the quenched theory. I then review lattice results for some quantities (the pion mass, pion scattering lengths and the K + → π + π 0 ...
متن کاملar X iv : h ep - p h / 97 10 46 8 v 2 1 2 N ov 1 99 7 Connections Between Lattice Gauge Theory and Chiral Perturbation Theory
In this talk, I address the comparison between results from lattice QCD computations and Chiral Perturbation Theory (ChPT). I briefly discuss how ChPT can be adapted to the much-used quenched approximation and what it tells us about the special role of the η ′ in the quenched theory. I then review lattice results for some quantities (the pion mass, pion scattering lengths and the K + → π + π 0 ...
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