The Mass of the η in selfdual QCD
نویسنده
چکیده
The QCD gauge field is modeled as an ensemble of statistically independent selfdual and antiselfdual regions. This model is motivated from instanton physics. The scale anomaly then allows to relate the topological susceptibility to the gluon condensate. With the help of Wittens formula for mη′ and an estimate of the suppression of the gluon condensate due to light quarks the mass of the η can be related to fπ and the physical gluon condensate. We get the quite satisfactory value mη′ = 884±116 MeV. Using the physical η ′ mass as an input it is in princple possible to get information about the interaction between instantons and anti-instantons. E–Mail:[email protected]–muenchen.de
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تاریخ انتشار 1995