Exclusive emissions of vector mesons in forward directions of rapidity offer us a faultless chance to probe the proton structure at small x. A high-energy factorization formula is established within BFKL, given as the convolution of an impact factor depicting the forward-meson emission and of an unintegrated gluon distribution (UGD) driving the gluon evolution at small x. As a nonperturbative quantity, the UGD is not well known and several models for it exist. We present recent progresses on the study of the exclusive forward ρ-meson leptoproduction at HERA and EIC energies, showing how osbervables sensitive to different polarization states of the ρ-particle act as discriminators for the existing UGD models.
Exclusive emissions of rho-mesons and the unintegrated gluon distribution
Alessandro PapaMembro del Collaboration Group
2022-01-01
Abstract
Exclusive emissions of vector mesons in forward directions of rapidity offer us a faultless chance to probe the proton structure at small x. A high-energy factorization formula is established within BFKL, given as the convolution of an impact factor depicting the forward-meson emission and of an unintegrated gluon distribution (UGD) driving the gluon evolution at small x. As a nonperturbative quantity, the UGD is not well known and several models for it exist. We present recent progresses on the study of the exclusive forward ρ-meson leptoproduction at HERA and EIC energies, showing how osbervables sensitive to different polarization states of the ρ-particle act as discriminators for the existing UGD models.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
