Non-perturbative large scale fluctuations of gluonic fields, which are present in the exact vacuum of QCD, result in a modification of the interaction between quarks in quarkonium. Such effects are considered for heavy quarks in cases when the size of the quarkonium system is much smaller than that of the dominating gluonic fluctuations. The Green function of relative motion in heavy quarkonium is calculated for energies below threshold taking account of leading non-perturbative effects. It is shown that once non-perturbative gluonic degrees of freedom are taken into consideration they can never be absorbed into a sort of interaction potential between quarks.
|Original language||English (US)|
|Number of pages||16|
|Journal||Nuclear Physics, Section B|
|State||Published - Aug 6 1979|