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arXiv · 2107.12725

Exclusive emissions of rho-mesons and the unintegrated gluon distribution

Andrèe Dafne Bolognino·Francesco Giovanni Celiberto·Dmitry Yu. Ivanov·Alessandro Papa
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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 $\rho$-meson leptoproduction at HERA and EIC energies, showing how osbervables sensitive to different polarization states of the $\rho$-particle act as discriminators for the existing UGD models.

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Andrèe Dafne Bolognino, Francesco Giovanni Celiberto, Dmitry Yu. Ivanov, Alessandro Papa. 2021-07-27. Exclusive emissions of rho-mesons and the unintegrated gluon distribution. https://doi.org/10.21468/scipostphysproc.8

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