We study the constraints that the operator product expansion imposes on large N c inspired QCD models for current-current correlators. We focus on the constraints obtained by going beyond the leading-order parton computation. We explicitly show that, assumed a given mass spectrum: linear Regge behavior in n (the principal quantum number) plus corrections in 1/n, we can obtain the logarithmic (and constant) behavior in n of the decay constants within a systematic expansion in 1/n. Our example shows that it is possible to have different large n behavior for the vector and pseudo-vector mass spectrum and yet comply with all the constraints from the operator product expansion. © SISSA 2007.
|Journal||Journal of High Energy Physics|
|Publication status||Published - 1 Oct 2007|
- Asymptotic freedom
- Phenomenological models
- Sum rules