0000000000040073
AUTHOR
J. Martin-camalich
Low-energy interactions of Nambu-Goldstone bosons with D mesons in covariant chiral perturbation theory
We calculate the scattering lengths of Nambu-Goldstone bosons interacting with D mesons in a covariant formulation of chiral perturbation theory, which satisfies heavy-quark spin symmetry and analytical properties of loop amplitudes. We compare our results with previous studies performed using heavy-meson chiral perturbation theory and show that recoil corrections are sizable in most cases.
The nucleon mass and pion-nucleon sigma term from a chiral analysis of Nf = 2+1 lattice QCD world data
Fits of the p^4 covariant SU(2) baryon chiral perturbation theory to lattice QCD nucleon mass data from several collaborations for 2 and 2+1 flavors are presented. We consider contributions from explicit Delta(1232) degrees of freedom, finite volume and finite spacing corrections. We emphasize here our Nf=2+1 study. We obtain low-energy constants of natural size that are compatible with the rather linear pion-mass dependence of the nucleon mass observed in lattice QCD. We report a value for the pion-nucleon sigma term of 41(5)(4) MeV for the 2 flavor case and 52(3)(8) MeV for 2+1 flavors.
Lowest-lying spin-1/2 and spin-3/2 baryon magnetic moments in chiral perturbation theory
5th International Conference on Quarks and Nuclear Physics (QNP09). Inst High Energy Phys Chinese Acad Sci, Beijing, PEOPLES R CHINA, SEP 21-25, 2009
THE NUCLEON MASS AND PION-NUCLEON SIGMA TERM FROM A CHIRAL ANALYSIS OF Nf = 2 + 1 LATTICE QCD WORLD DATA
Fits of the p4 covariant SU(2) baryon chiral perturbation theory to lattice QCD nucleon mass data from several collaborations for 2 and 2+1 flavors are presented. We consider contributions from explicit Δ(1232) degrees of freedom, finite volume and finite spacing corrections. We emphasize here on our Nf = 2 + 1 study. We obtain low-energy constants of natural size that are compatible with the rather linear pion-mass dependence of the nucleon mass observed in lattice QCD. We report a value of σπN = 41(5)(4) MeV in the 2 flavor case and σπN = 52(3)(8) MeV for 2+1 flavors.
Nucleon andΔ(1232)form factors at low momentum transfer and small pion masses
An expansion of the electromagnetic form factors of the nucleon and $\ensuremath{\Delta}(1232)$ in small momentum transfer and pion mass is performed in a manifestly covariant EFT framework consistent with chiral symmetry and analyticity. We present the expressions for the nucleon and $\ensuremath{\Delta}(1232)$ electromagnetic form factors, charge radii, and electromagnetic moments in the framework of $SU(2)$ baryon chiral perturbation theory, with nucleon and $\ensuremath{\Delta}$-isobar degrees of freedom, to next-to-leading order. Motivated by the results for the proton electric radius obtained from the muonic-hydrogen atom and electron-scattering process, we extract values for the seco…