The role of finite-size effects on the spectrum of equivalent photons in proton-proton collisions at the LHC

Understand

Photon-photon interactions represent an important class of physics processes at the LHC, where quasi-real photons are emitted by both colliding protons.

• These reactions can result in the exclusive production of a final state $X$, $p+p \rightarrow p+p+X$.
• When computing such cross sections, it has already been shown that finite size effects of colliding protons are important to consider for a realistic estimate of the cross sections.
• These first results have been essential in understanding the physics case of heavy-ion collisions in the low invariant mass range, where heavy ions collide to form an exclusive final state like a $J/\Psi$ vector meson.