Global Bayesian Analysis of $\mathrm{J}/\ddot{I}ˆ$ Photoproduction on Proton and Lead Targets

Abstract

We perform a global Bayesian analysis of diffractive $\mathrm{J}/\ddot{I}ˆ$ production in ${\hat{I}}^3+p$ and ${\hat{I}}^3+\mathrm{Pb}$ collisions using a color glass condensate (CGC) based calculation framework. As past calculations have shown that CGC-based models typically overpredict the $\mathrm{J}/\ddot{I}ˆ$ production in ${\hat{I}}^3+\mathrm{Pb}$ collisions at high center of mass energy, we address the question of whether it is possible to describe coherent and incoherent diffractive $\mathrm{J}/\ddot{I}ˆ$ data from ${\hat{I}}^3+p$ collisions at HERA and the LHC, and from ${\hat{I}}^3+\mathrm{Pb}$ collisions at the LHC simultaneously. Our results indicate that a simultaneous description of ${\hat{I}}^3+p$ and ${\hat{I}}^3+\mathrm{Pb}$ data is challenging, with results improving when an overall $K$-factor -- scaling ${\hat{I}}^3+p$ and ${\hat{I}}^3+\mathrm{Pb}$ cross sections to absorb model uncertainties -- is introduced.

16 pages, 4 figures