Measurement of light-by-light scattering and the Breit-Wheeler process, and search for axion-like particles in ultraperipheral PbPb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV

CMS Collaboration

Measurements of light-by-light scattering (LbL, ${\hat{I}}^3{\hat{I}}^3$ $\to$ ${\hat{I}}^3{\hat{I}}^3$) and the Breit-Wheeler process (BW, ${\hat{I}}^3{\hat{I}}^3$ $\to$ ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$) are reported in ultraperipheral PbPb collisi…