Significance of gluon density for soft and hard processes at LHC

Apr 14, 2016, 9:45 AM
Auditorium (DESY Hamburg)


DESY Hamburg

Structure Functions and Parton Densities WG1 Structure Functions and Parton Densities


Prof. Gennady Lykasov (JINR)


We study the role of the non-perturbative input to the transverse momentum dependent (TMD) gluon density in hard processes at the LHC. We derive the input TMD gluon distribution at a low scale $\mu_0^2 \sim 1$~GeV$^2$ from a fit of inclusive hadron spectra measured at low transverse momenta in $pp$ collisions at the LHC and demonstrate that the best description of these spectra for larger hadron transverse momenta can be achieved by matching the derived TMD gluon distribution with the exact solution of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation obtained at low $x$ and small gluon transverse momenta outside the saturation region, see for example [1]. Then, we extend the input TMD gluon density to higher $\mu^2$ numerically using the Catani-Ciafoloni-Fiorani-Marchesini (CCFM) gluon evolution equation. Special attention is paid to phenomenological applications of the obtained TMD gluon density to some LHC processes, which are sensitive to the gluon content of a proton [2]. References. [1] Yu.V.Kovchegov, Phys. Rev. D61, 074018 (2000). [2] A.A.Grinyuk, A.V.Lipatov, G.I.Lykasov, N.P.Zotov, Phys. Rev. D93, 014035 (2016).


The new unintegrated gluon density (MD2015) is proposed. Its application to the analysis of the DIS and inelastic p-p processes at the LHC energies allows us to describe rather satisfactorily the charm and beauty contribution to the proton structure function F2 and the longitudinal structure function FL, and many observables on the soft and hard p-p reactions.

Primary authors

Dr Artem Lipatov (Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, 119991 Moscow, Russia) Prof. Gennady Lykasov (JINR)


Mr Andrei Grinyuk (JINR) Dr Nikolai Zotov (Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, 119991 Moscow, Russia)

Presentation materials