Extended NJL model with eight-quark interactions

Abstract

We present the results obtained in the three-flavour ($N_f=3$) Nambu--Jona-Lasinio model which is extended by the $U(1{)}_A$ breaking six-quark 't Hooft interaction and eight-quark interactions. We address the problem of stability, and some phenomenological consequences of the models with multi-quark interactions.

Comments: 4 pages, prepared for the "Mini-Workshop Bled 2009: Problems in multi-quark states"