Speaker
Prof.
Fabio L. Braghin
(UFG)
Description
Higher order quark effective interactions, correcting the usual NJL interaction, are derived by considering polarization effects [1,2,3]. A set of auxiliary fields is introduced one of which yields the scalar chiral quark-antiquark condensate. Fluctuations are shown to provide effective quark couplings. The leading fourth order coupling provides a correction the Nambu-Jona-Lasinio model. The sixth order interaction corresponds to the ‘t Hooft interaction and the eighth order ones correspond to already known chiral invariant quark interactions. Other chiral invariant quark-quark couplings are found. The precise shape of the gluon propagator is not necessarily relevant for the shape of the resulting effective couplings although it might be important for numerical estimations.
References:
F.L. Braghin, submitted to publication and in preparation. E. Barros Jr., F.L. Braghin, Phys. Rev. D 88, 034011 (2013). A. Paulo Jr., F.L. Braghin, Phys. Rev. D 90, 014049 (2014). A.A. Osipov, B. Hiller, J. Moreira and A.H. Blin, Eur. Phys. J. C 46, 225 (2006). A. Manohar, H. Georgi, Nucl. Phys. B 234, 189 (1984).C.D. Roberts, R.T. Cahill, J. Praschifka, Ann. of Phys. 188, 20 (1988). S. Weinberg, Phys. Rev. Lett. 105, 261601 (2010).
Author
Prof.
Fabio L. Braghin
(UFG)
