Hyperon-nucleon coupling from QCD sum rules

Abstract

The NKY coupling constant for $Y=\Lambda$ and $\Sigma$ is evaluated in a QCD sum rule calculation. We discuss and extend the result of a previous analysis in the $\text{/}qi{\gamma }_5$ structure and compare it with the result obtained with the use of the ${\gamma }_5{\sigma }_{\mu \nu }$ structure. We find a huge violation of the SU(3) symmetry in the ${\gamma }_5{\sigma }_{\mu \nu }$ structure.

Comments: 4 pages, 2 figures, espcrc2.sty included. Talk presented at QCD99, Montpellier, France (to appear in Nucl.Phys.B Proc.Suppl.)