Three-photon productions within the $$k_t$$-factorization at the LHC

Abstract Recently, the ATLAS data of isolated three-photon production showed that next-to-leading order (NLO) collinear factorization is not enough to describe experimental data. Therefore, one needs calculate cross section beyond NLO, and as later, these can be well described by NNLO calculation within framework. However, it shown $$k_t$$ k t -factorization quite successful in describing exclusive high energy collision processes, henceforth we decided this In work use Martin, Ryskin, Watt unintegrated parton distribution functions (MRW UPDFs) at LO NLO levels, addition branching (PB) UPDFs which utilize KATIE level event generator. It will contrast factorization, quiet Interestingly our results using NLO-MRW PB cover their uncertainty bands, similar results.