XXVIII International Workshop on Deep-Inelastic Scattering and Related Subjects

Momentum transfer dependence of heavy quarkonium electroproduction

15 Apr 2021, 08:54

18m

Virtual (Stony Brook, NY)

Contributed Talk Small-x, Diffraction and Vector Mesons Small-x, Diffraction and Vector Mesons

Speaker

Michal Krelina (FNSPE Czech Technical University in Prague)

Description

We investigate the momentum transfer dependence of differential cross sections $d\sigma /dt$ in diffractive electroproduction of heavy quarkonia.

The calculations have been performed within the light-front QCD dipole formalism using realistic quarkonium wave functions determined from various potential models in the $Q\overline{Q}$ rest frame.

Model predictions for $d\sigma /dt$ including a proper correlation between the impact parameter $\overrightarrow{b}$ of a collision and color dipole orientation $\overrightarrow{r}$ are compared with available HERA data.

We analyze the impact of a realistic $\overrightarrow{b}$-$\overrightarrow{r}$ correlation on results for $d\sigma (t)/dt$ by comparing with conventional dipole models including only additional factorized $b$- dependent part and with recent calculations based on a popular Balitzky-Kovchegov model, where such a correlation is not incorporated accurately.

We have demonstrated that the effect of $\overrightarrow{b}$-$\overrightarrow{r}$ correlation is boosted in the production of radially excited charmonia due to the nodal structure of their radial wave functions.

Experimental investigation of the ${\psi }^{\prime }(2S)$-to-$J/\psi (1S)$ ratio of $t$-dependent differential cross sections can shed more light on the onset of $\overrightarrow{b}$-$\overrightarrow{r}$ correlation within various dipole models, as well as on manifestation of saturation effects at small $x$.

Presentation materials

DIS2021-Krelina-v1.pdf

Youtube Link