Pseudoscalar glueball wave functions from QCD sum rules

Abstract
Using QCD sum rules, we calculate the first few moments of the distribution amplitude of a pseudoscalar glueball, in the approximation that the glueball is narrow. These moments then give the corresponding first few coefficients of the distribution amplitude for the glueball expanded in Gegenbauer polynomials. The distribution amplitude is rather close to its asymptotic form, and the glueball's "decay constant" is about 105 MeV for a pseudoscalar glueball mass of 2.0 GeV.