Nuclear modifications of parton distributions

5 May 2026, 17:45
20m
Sala IMPERIALE A, First Floor (Hotel Carlton)

Sala IMPERIALE A, First Floor

Hotel Carlton

Talk WG1 Structure Functions and Parton Densities WG1 Structure functions and parton densities

Speaker

Roberto Petti

Description

A quantitative explanation of the effects observed in nuclear DIS requires the presence of an in-medium nuclear modification of parton distribution functions, extending beyond the traditional Fermi motion and binding correction. We will discuss nuclear DIS basing on a microscopic model [1] taking into account the energy-momentum spectrum of bound nucleons, off-shell modification of bound nucleon structure functions, corrections from meson-exchange currents as well as the corrections from propagation of quark-gluon states in nuclear environment. The off-shell correction, which provides a mechanism of the modifications of the partonic structure in bound protons and neutrons, can be constrained from a global QCD analysis together with the PDFs in the proton. The new data from MARATHON experiment on the EMC effect for 3He/2H and 3H/2H allows to better constrain F2n/F2p in the region of large Bjorken x, as well as to improve the accuracy in the determination of the isoscalar nucleon off-shell function, its proton-neutron asymmetry, and ts interplay with the higher-twist terms in the structure functions. We discuss a number of applications including lepton-nucleus DIS, Drell-Yan production in proton-nucleus collisions, and $W^\pm, Z^0$ boson production in p+Pb collisions at the LHC.

References

[1] S.A. Kulagin and R. Petti, Nucl. Phys. A765 (2006) 126.
[2] S.I. Alekhin, S.A. Kulagin, R.Petti, Phys. Rev. D96 (2017) 054005.
[3] S.I. Alekhin, S.A. Kulagin, R.Petti, Phys. Rev. D105 (2022) 114037.
[4] S.I. Alekhin, S.A. Kulagin, R.Petti, Phys. Rev. D107 (2023) L051506.

Speaker confirmation Yes

Authors

Roberto Petti Sergey Alekhin (Institute for High Energy Physics (Protvino, Russia)) Sergey Kulagin (INR, Moscow, Russia)

Presentation materials