Factorization of photon induced processes in ultra-peripheral heavy ion collisions

Abstract

In this study, we investigate photon-photon scattering in ultra-peripheral heavy ion collisions (UPCs). We start by deriving an effective Lagrangian from first principles and then apply factorization techniques from Soft-Collinear effective theory (SCET). This approach allows us to decompose the photon-photon scattering cross-section into two primary factors: the generalized transverse momentum distributions (GTMDs) and the hard scattering amplitude. We further analyze the emission of soft photons by final state leptons, incorporating a soft function into the cross section through an evolution method. Our analysis yields detailed predictions for observable angular correlations among the final state leptons. Specifically, we calculate the angular correlations characterized by the azimuthal parameters $⟨\cos 2\varphi ⟩$ and $⟨\cos 4\varphi ⟩$, highlighting the influence of initial photons polarization and recoil effects from final state soft photons.

References in corpus (9)

• Glauber Modeling in High Energy Nuclear Collisions
• Hadronic contribution to the muon anomalous magnetic moment to next-to-next-to-leading order
• Effective field theory interpretation of lepton magnetic and electric dipole moments
• Determining the leading-order contact term in neutrinoless double $\mathbf{\beta }$ decay
• Impact parameter dependence of the azimuthal asymmetry in lepton pair production in heavy ion collisions
• Electron and Muon Anomalous Magnetic Moments in the Inverse Seesaw Extended NMSSM
• Lepton pair photoproduction in peripheral relativistic heavy-ion collisions
• Azimuthal asymmetries of muon pair production in ultraperipheral heavy ion collisions
• Factorization and transverse phase-space parton distributions