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arXiv · hep-ph/9903485

$π- π$ Scattering Lengths and Chiral Condensate in NJL Model

Mei Huang·Pengfei Zhuang·Weiqin Chao
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Abstract

Within the general framework of SU(2) Nambu-Jona-Lasinio model beyond mean-field approximation, the S-wave $π- π$ scattering lengths $a_0^0$ and $a_0^2$ are calculated. The numerical results are in agreement with that analyzed from recent experiment $πN \to ππN$ data by using Chew-Low-Goebel technique, and the corresponding chiral condensate $<{\bar q}q>$ is around $-(250 {\rm MeV})^3$, which is close to the ones obtained from lattice and sum rules.

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Mei Huang, Pengfei Zhuang, Weiqin Chao. 1999-03-25. $π- π$ Scattering Lengths and Chiral Condensate in NJL Model. https://arxiv.org/abs/hep-ph/9903485

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