Inelastic photoproduction of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mfrac><mml:mrow><mml:mi>J</mml:mi></mml:mrow><mml:mrow><mml:mi>ψ</mml:mi></mml:mrow></mml:mfrac></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>ϒ</mml:mi></mml:math>by gluons

Amplitudes are derived for the quantum-chromodynamic subprocess $\ensuremath{\gamma}g\ensuremath{\rightarrow}(\frac{J}{\ensuremath{\psi}})g$, with a specific wave function used to represent the $\frac{J}{\ensuremath{\psi}}$ as a $c\overline{c}$ system. The results are used to obtain the normalized total cross section ${\ensuremath{\sigma}}_{\ensuremath{\gamma}}$ for the inelastic process $\ensuremath{\gamma}N\ensuremath{\rightarrow}(\frac{J}{\ensuremath{\psi}})X$, predictions for the $z$ and ${p}_{T}$ dependence of inelastic $\frac{J}{\ensuremath{\psi}}$ photoproduction, and predictions for the $\frac{J}{\ensuremath{\psi}}$ helicity. The predictions apply as well to electroproduction at small ${Q}^{2}$.

Not yet translated