Constituent quark masses from modified perturbative QCD
Instituto de Cibernética, Matemàtica y Fìsica, Calle E, No. 309, Vedado, La Habana, Cuba
2 International Institute for Theoretical and Applied Physics (IITAP), UNESCO and Iowa State University, Ames, IA 50011, USA
3 Centro de Estudios Aplicados al Desarrollo Nuclear, Calle 30, N. 502 e/ 5ta y 7ma, Miramar, La Habana, Cuba
Revised: 15 November 2001
Published online: 8 February 2002
A recently proposed modified perturbative expansion for QCD incorporating gluon condensation is employed to evaluate the quark and gluon self-energy corrections in first approximation. The results predict mass values of 1/3 of the nucleon mass for the light quarks u, d, and s and a monotonously growing variation with the current mass. The only phenomenological input is that 〈G2〉 is evaluated up to order g2as a function of the unique parameter C defining the modified propagator, and then C is fixed to give a current estimate of 〈g2G2〉. The light quarks u and d as a result are found to be confined and the s, c, b and t ones show damped propagation modes, suggesting a model for the large differences in stability between the nucleons and the higher resonances. The above properties of quark modes diverge from the fully confinement result following from the similar gluon propagator previously considered by Munczek and Nemirovski. On the other hand, the condensate effects on the gluon self-energy furnish a tachyonic mass shell as predicted by the Fukuda analysis of gluon condensation in QCD.
© Società Italiana di Fisica, Springer-Verlag, 2002