Speaker
Description
Results of nuclear modification of Upsilon production in pPb collisions at 5.02 TeV and exclusive Upsilon photoproduction in Ultraperipheral collisions (UPC) of pPb at 8.16 TeV, are presented. The nuclear modification factors in pPb collisions are measured to quantify nuclear effects in such a small system and sequential suppression is observed among the three states following the ordering of their binding energies. Exclusive photoproduction of Upsilon states in UPC of protons and Pb using data collected by the CMS in 2016 with an integrated luminosity of $178.4 $ nb$^{-1}$, is presented. The $\Upsilon(1S)$ photoproduction cross-section is extracted in the region $|y|<2.2$ as a function of the photon-proton centre-of-mass energies $W_{\gamma p}$, which provides valuable information of the gluon distribution at small values of parton fractional momenta $x$. The results are compared to other experimental results as well as various theoretical predictions.
| Contribution type | Contributed Talk |
|---|---|
| Track | Heavy Flavor and Quarkonia |
| Collaboration (if applicable) | CMS |
