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arXiv · 1701.06018

Meson-baryon scattering to one-loop order in heavy baryon chiral perturbation theory

Bo-Lin Huang·Jin-Sheng Zhang·Yun-De Li·Norbert Kaiser
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Abstract

We calculate the T-matrices of pseudoscalar meson octet-baryon scattering to one-loop order in SU(3) heavy baryon chiral perturbation theory. The pertinent combinations of low-energy constants are determined by fitting to phase shifts of $\pi N$ and $K N$ scattering and the corresponding data. By using these low-energy constants, we obtain the strong phase shift difference of $\pi \Lambda$ scattering at the $\Xi$ mass, $\delta_P-\delta_S=(8.8 \pm 0.2)$ degrees, in agreement with experimental results. We find that the phase shifts in the $S_{01}$($\pi \Sigma$), $S_{01}$($K \Xi$), $S_{01}$($\overline{K} N$), and $S_{11}$($\overline{K} \Sigma$) waves are so strong that resonances may be generated dynamically in all these channels. We also predict the scattering lengths and make comparisons with the results obtained from the threshold T-matrices in heavy baryon chiral perturbation theory and the method of covariant infrared regularization. The issue of convergence is also discussed in detail.

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Bo-Lin Huang, Jin-Sheng Zhang, Yun-De Li, Norbert Kaiser. 2017-01-21. Meson-baryon scattering to one-loop order in heavy baryon chiral perturbation theory. https://doi.org/10.1103/physrevd.96.016021

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