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arXiv · 1302.1953

Virtual decuplet effects on octet baryon masses in covariant baryon chiral perturbation theory

Xiu-Lei Ren·Lisheng Geng·Jie Meng·Hiroshi Toki
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Abstract

We extend a previous analysis of the lowest-lying octet baryon masses in covariant baryon chiral perturbation theory (ChPT) by explicitly taking into account the contribution of the virtual decuplet baryons. Up to next-to-next-to-next-to-leading order (N$^3$LO), the effects of these heavier degrees of freedom are systematically studied. Their effects on the light-quark mass dependence of the octet baryon masses are shown to be relatively small and can be absorbed by the available low-energy constants up to N$^3$LO. Nevertheless, a better description of the finite-volume corrections of the lattice QCD data can be achieved, particularly those with small $M_ϕL$ ($<4$), which is demonstrated by a careful study of the NPLQCD and QCDSF-UKQCD small-volume data. Finally, we show that the predicted pion- and strangeness-baryon sigma terms are only slightly changed by the inclusion of the virtual decuplet baryons.

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Xiu-Lei Ren, Lisheng Geng, Jie Meng, Hiroshi Toki. 2013-02-08. Virtual decuplet effects on octet baryon masses in covariant baryon chiral perturbation theory. https://doi.org/10.1103/physrevd.87.074001

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