BB intermeson potentials in the quark model
/ Abstract
In this paper we derive quark model results for scattering amplitudes and equivalent low energy potentials for heavy meson pairs, in which each meson contains a heavy quark. This {open_quotes}BB{close_quotes} system is an attractive theoretical laboratory for the study of the nuclear force between color singlets; the hadronic system is relatively simple, and there are lattice gauge theory (LGT) results for V{sub BB}(r) which may be compared to phenomenological models. We find that the quark model potential (after lattice smearing) has qualitative similarities to the LGT potential in the two B{sup {asterisk}}B{sup {asterisk}} channels in which direct comparison is possible, although there is evidence of a difference in length scales. The quark model prediction of equal magnitude but opposite sign for I=0 and I=1 potentials also appears similar to LGT results at intermediate {ital r}. There may however be a discrepancy between the LGT and quark model I=1 BB potentials. A numerical study of the two-meson Schr{umlt o}dinger equations in the (b{bar q})(b{bar q}) and (c{bar q})(c{bar q}) sectors with the quark model potentials finds a single BB {open_quotes}molecule,{close_quotes} in the I=0 BB{sup {asterisk}} sector. Binding in other channels might occur if the quark model forces are augmented by pion more » exchange. {copyright} {ital 1999} {ital The American Physical Society} « less
Journal: Physical Review C