TY  - JOUR
AU  - Ledwig, T.
AU  - Martin Camalich, J.
AU  - Geng, L. S.
AU  - Vicente Vacas, M. J.
PY  - 2014
DA  - 2014//
TI  - Octet-baryon axial-vector charges and SU(3)-breaking effects in the semileptonic hyperon decays
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 054502
EP  - 16pp
VL  - 90
IS  - 5
PB  - Amer Physical Soc
AB  - The octet-baryon axial-vector charges and the g(1)/f(1) ratios measured in the semileptonic hyperon decays are studied up to O(p(3)) using the covariant baryon chiral perturbation theory with explicit decuplet contributions. We clarify the role of different low-energy constants and find a good convergence for the chiral expansion of the axial-vector charges of the baryon octet, g(1)(0), with O(p(3)) corrections typically around 20% of the leading ones. This is a consequence of strong cancellations between different next-to-leading- order terms. We show that considering only nonanalytic terms is not enough and that analytic terms appearing at the same chiral order play an important role in this description. The same effects still hold for the chiral extrapolation of the axial-vector charges and result in a rather mild quark-mass dependence. As a result, we report a determination of the leading-order chiral couplings, D = 0.623(61)(17) and F = 0.441(47)(2), as obtained from a completely consistent chiral analysis up to O(p(3)). Furthermore, we note that the appearance of an unknown low-energy constant precludes the extraction of the proton octet charge from semileptonic decay data alone, which is relevant for an analysis of the composition of the proton spin.
SN  - 1550-7998
UR  - http://arxiv.org/abs/arXiv:1405.5456
UR  - https://doi.org/10.1103/PhysRevD.90.054502
DO  - 10.1103/PhysRevD.90.054502
LA  - English
N1  - WOS:000341264600001
ID  - Ledwig_etal2014
ER  -