Workshop introduction

• Laurent Forthomme (AGH University of Krakow (PL))
• Hamzeh Khanpour (AGH University of Science and Technology)
• Krzysztof Piotrzkowski (AGH University (Kraków, PL))

Room: D-10 D-czarna

Exploring High Energy Photon-Photon Interactions at the LHeC

• Hamzeh Khanpour (AGH University of Science and Technology)

Room: D-10 D-czarna The future Large Hadron-Electron Collider (LHeC) provides a unique platform to explore high-energy photon-photon ($\gamma \gamma$) interactions in electron-proton collisions. This talk focuses on the exclusive production of lepton pairs and the potential to probe supersymmetric particles, such as higgsinos, through photon-induced processes. Utilizing the Equivalent Photon Approximation (EPA), we investigate the kinematic properties and cross-sections of such interactions. Additionally, we compare our calculations based on EPA with predictions from various event generators, including cepgen/Lpair, and GRAPE, demonstrating excellent agreement. The high luminosity and clean environment of the LHeC make it an ideal laboratory for testing photon-induced processes, providing valuable insights into electroweak interactions and possible extensions of the SM.

Production of exclusive dijets at electron-proton colliders

• Antoni Szczurek

Room: D-10 D-czarna

Photon transition form factors of C-even quarkonia for virtual photons

• Wolfgang Schaefer

Room: D-10 D-czarna

Virtual Compton scattering processes in upcoming experiments

• Paweł Sznajder (National Centre for Nuclear Research)

Room: D-10 D-czarna In my talk, I will describe recent progress in the study of a family of virtual Compton scattering (VCS) processes within the framework of generalized parton distributions (GPDs). This includes deeply virtual Compton scattering (DVCS), timelike Compton scattering (TCS), and double deeply virtual Compton scattering (DDVCS). I will also focus on the measurability of these processes in upcoming JLab and EIC experiments. In particular, I will present preliminary impact studies for DVCS at EIC.

𝛾𝛾 → µ+µ-, 𝜏+𝜏- at EIC

• Krzysztof Piotrzkowski (AGH University (Kraków, PL))

Room: D-10 D-czarna The two-photon exclusive production of lepton pairs at the Electron–Ion Collider will open interesting research directions thanks to a very high luminosity and clean experimental conditions. A survey of the scientific potential of such studies is reported. In particular, we consider unique measurements of the proton elastic electromagnetic form-factors and a possibility of studying the anomalous electromagnetic dipole moments of tau leptons.

Two-photon physics with the CepGen event generator and 𝛾𝛾 → W+W-/ZZ at LHC and LHeC

• Laurent Forthomme (AGH University of Krakow (PL))

Room: D-10 D-czarna CepGen is a matrix element level Monte Carlo generator intended for the simulation of central exclusive processes (and in particular $\gamma\gamma$) at LHC. In the recent years, numerous extensions allowed it to simulate an even broader range, e.g. diffraction and UPC interactions. In this talk, the generator will be presented along its modular extensions capability, allowing e.g. the definition of new processes, and incoming partons fluxes modellings, or interfacing to existing libraries.

Topical discussion Room: D-10 D-czarna * Precise simulation of Bethe-Heitler two-photon production of lepton pairs at polarised EIC * Tau-tau production & decay at EIC * Nuclear effects in gamma-gamma to lepton pairs at eA@EIC * Tau-tau final state analysis at LHeC * Two-photon production of W, or Z pairs at LHeC (incl. 2-to-6 simulation) * Photoproduction of t-tbar at LHeC * Event generators developments