Abstract

The intense photon fluxes of relativistic nuclei provide a possibility to study photonuclear and two-photon interactions in ultra-peripheral collisions (UPC) where the nuclei do not overlap and no strong nuclear interactions occur. The study of such collisions provides information about the initial state of nuclei. First ALICE results from the LHC Run 2 are presented for forward exclusive \jpsi production in UPC, which is sensitive to the gluon distribution in nuclei. The increased statistics and the higher collision energy allows for a more detailed study at lower values of Bjorken-$x$. The analysis of the $\gamma+A \rightarrow \rho^0+A$ process in UPC is a tool to test the so-called black disk regime, where the target nucleus appears like a black disk and the total $\rho^0+A$ cross section reaches its limit. ALICE reports new measurements of \rrho photoproduction cross sections in Pb-Pb UPC at $\sqrt{s_{\rm NN}}=5.02$ TeV at mid-rapidity, which are compared to predictions.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.