Orateur
M.
Xiu-Lei REN
(IPN Orsay)
Description
We study the ground-state octet baryon masses and sigma terms using the covariant baryon chiral perturbation theory (ChPT) with the extended-on-mass-shell (EOMS) renormalization scheme up to next-to-next-to-next-to-leading order (N$^3$LO). In order to systematically study the lattice QCD data and to fix the low-energy constants (LECs), the finite-volume corrections (FVCs) and finite lattice spacing discretization effects of LQCD simulations are included self-consistently.
Through a simultaneous fit of all the publicly available $n_f = 2+1$ lattice QCD data from the PACS-CS, LHPC, HSC, QCDSF-UKQCD and NPLQCD collaborations, it shows that the N$^3$LO EOMS BChPT can give a reasonable fit with $\chi^2/\mathrm{d.o.f.} = 1.0$ and the various lattice simulations seem to be consistent with each other. We also conclude that the finite lattice spacing discretization effects up to $\mathcal{O}(a^2)$ can be safely ignored. Finally, the octet baryon sigma terms are predicted via the Feynman-Hellmann theorem. In particular, the pion- and strangeness-nucleon sigma terms are $\sigma_{\pi N} = 55(1)(4)$ MeV and $\sigma_{sN} = 27(27)(4)$ MeV, respectively.
Auteur principal
M.
Xiu-Lei REN
(IPN Orsay)
Co-auteurs
Prof.
Jie MENG
(Peking University)
Prof.
Li-Sheng GENG
(Beihang University)
