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arXiv · 1405.4990

Octet baryon masses and sigma terms in covariant baryon chiral perturbation theory

Xiu-Lei Ren·Li-Sheng Geng·Jie Meng
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Abstract

We report an analysis of the octet baryon masses using the covariant baryon chiral perturbation theory up to next-to-next-to-next-to-leading order with and without the virtual decuplet contributions. Particular attention is paid to the finite-volume corrections and the finite lattice spacing effects on the baryon masses. A reasonable description of all the publicly available $n_f=2+1$ lattice QCD data is achieved.Utilyzing the Feynman-Hellmann theorem, we determine the nucleon sigma terms as $\sigma_{\pi N}=55(1)(4)$ MeV and $\sigma_{sN}=27(27)(4)$ MeV.

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Xiu-Lei Ren, Li-Sheng Geng, Jie Meng. 2014-05-20. Octet baryon masses and sigma terms in covariant baryon chiral perturbation theory. https://doi.org/10.1142/9789814618229_0033

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