Hadron structure at small-x via unintegrated gluon densities


  • A. Dafne Bolognino Universita della Calabria and Istituto Nazionale di Fisica Nucleare
  • F. Giovanni Celiberto European Centre for Theoretical Studies in Nuclear Physics and Related Areas
  • Michael Fucilla Università della Calabria
  • D. Yu. Ivanov Sobolev Institute of Mathematics
  • A. Papa Universita della Calabria and Istituto Nazionale di Fisica Nucleare
  • W. Shäfer Institute of Nuclear Physics Polish Academy of Sciences
  • A. Szczurek College of Natural Sciences, Institute of Physics, University of Rzeszow




Hadron structure, Quantum Chromodynamics at small x


Inclusive as well as exclusive emissions in forward and central directions of rapidity are widely recognized as excellent channels to access the proton structure at small x. In this regime, to describe nucleons structure, it is necessary to use kT -unintegrated distributions. In particular, at large transverse momenta, the x-evolution of the so-called unintegrated gluon distribution is driven by the Balitsky-Fadin-Kuraev-Lipatov equation, within the framework of the high-energy factorization (HEF). Recent analyses on the diffractive electroproduction of ρ mesons have corroborated the underlying assumption that the small-size dipole scattering mechanism is at work, thus validating the use of the HEF formalism. Nonetheless, a significant sensitivity of polarized cross sections to intermediate values of the meson transverse momenta, where, in the case of inclusive emissions, a description at the hand of the transverse momentum dependent (TMD) factorization starts to be the most appropriate framework, has been observed. In this work, we will review the formal description of the UGD within the BFKL approach and present some UGD models that have been proposed, then we will describe the state of the art of some recent phenomenological analyses.


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How to Cite

Dafne Bolognino A, Giovanni Celiberto F, Fucilla M, Yu. Ivanov D, Papa A, Shäfer W, Szczurek A. Hadron structure at small-x via unintegrated gluon densities. Supl. Rev. Mex. Fis. [Internet]. 2022 Jun. 8 [cited 2024 May 20];3(3):0308109 1-5. Available from: https://rmf.smf.mx/ojs/index.php/rmf-s/article/view/6292