Constraint on the light quark mass mq from QCD sum rules in the I=0 scalar channel
| Autor: | Jia-Min Yuan, Hong-Ying Jin, T. G. Steele, Zhu-Feng Zhang, Zhuo-Ran Huang |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Physics
Quantum chromodynamics QCD sum rules Particle physics 010308 nuclear & particles physics Scalar (mathematics) Hadron Spectral density Particle Data Group 01 natural sciences Pseudoscalar 0103 physical sciences High Energy Physics::Experiment Sum rule in quantum mechanics 010306 general physics |
| Zdroj: | Physical Review D. 96 |
| ISSN: | 2470-0029 2470-0010 |
| Popis: | In this paper, we reanalyze the $I=0$ scalar channel with the improved Monte-Carlo-based QCD sum rules, which combines the rigorous H\"older-inequality-determined sum rule window and a parametrization with two-Breit-Wigner-type resonances for the phenomenological spectral density that satisfies the low-energy theorem for the scalar form factor. Considering the uncertainties of the QCD parameters and the experimental masses and widths of the scalar resonances $\ensuremath{\sigma}$ and ${f}_{0}(980)$, we obtain a prediction for light quark mass ${m}_{q}(2\text{ }\text{ }\mathrm{GeV})=\frac{1}{2}({m}_{u}(2\text{ }\text{ }\mathrm{GeV})+{m}_{d}(2\text{ }\text{ }\mathrm{GeV}))={4.7}_{\ensuremath{-}0.7}^{+0.8}\text{ }\text{ }\mathrm{MeV}$, which is consistent with the Particle Data Group value and QCD sum rule determinations in the pseudoscalar channel. This agreement provides a consistent framework connecting QCD sum rules and low-energy hadronic physics. We also obtain the decay constants of $\ensuremath{\sigma}$ and ${f}_{0}(980)$ at 2 GeV, which are approximately 0.64--0.83 and 0.40--0.48 GeV, respectively. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|