Refined TMD gluon density in a proton from the HERA and LHC data

A. V. Lipatov; G. I. Lykasov; M. A. Malyshev

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arXiv · 2404.09550

Refined TMD gluon density in a proton from the HERA and LHC data

A. V. Lipatov·G. I. Lykasov·M. A. Malyshev

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Abstract

We update the phenomenological parameters of the Transverse Momentum Dependent (TMD, or unintegrated) gluon density in a proton proposed in our previous studies. This analysis is based on the analytical expression for starting gluon distribution which provides a self-consistent simultaneous description of HERA data on proton structure function $F_2(x,Q^2)$, reduced cross section for the electron-proton deep inelastic scattering at low $Q^2$ and soft hadron production in $pp$ collisions at the LHC conditions. We extend it to the whole kinematical region using the Catani-Ciafaloni-Fiorani-Marchesini (CCFM) evolution equation. Exploiting our previous results on a number of semihard QCD processes, we performed a combined fit to an extended set of LHC and HERA data, comprising a total of $509$ points from $16$ data sets. We illustrate our fit by applying the derived TMD gluon density in a proton to inclusive prompt photon photoproduction at HERA.

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A. V. Lipatov, G. I. Lykasov, M. A. Malyshev. 2024-04-15. Refined TMD gluon density in a proton from the HERA and LHC data. https://arxiv.org/abs/2404.09550

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