Nuclear effects in the deuteron and constraints on the d/u ratio

Abstract

We present a detailed study of nuclear corrections in the deuteron (D) by performing an analysis of data from deep inelastic scattering off proton and D, dilepton pair production in pp and pD interactions, and W ± and Z boson production in pp and pp collisions. In particular, we discuss the determination of the off-shell function describing the modification of the parton distribution functions in bound nucleons in the context of global QCD fits. Our results are consistent with the ones obtained independently from the study of data on deep inelastic scattering off heavy nuclei with mass number A ≥ 4, further confirming the universality of the off-shell function of the bound nucleon. We also study the sensitivity to the modeling of the deuteron wave function. As an important application we discuss the impact of nuclear corrections to the deuteron on the determination of the d quark distribution.

Applications of KP Nuclear Parton Distributions

“…This comparison illustrates the relevance of the OS correction, which, together with the Fermi-motion and nuclear binding correction, provides a quantitative description of the observed EMC effect. An independent study from DIS off proton and deuteron targets confirms the universality of the δ f function [7]. We also note that high-twist corrections [13] as well as target-mass corrections play a significant role in the results of Refs.…”

“…We also note that high-twist corrections [13] as well as target-mass corrections play a significant role in the results of Refs. [2,5,7].…”

“…This model explains to a high accuracy the observed x, Q and A dependencies of the measured nuclear effects in deep-inelastic scattering (DIS) on a wide range of targets from deuterium to lead [2,4,5,7]; the magnitude, the x and mass dependence of available data from Drell-Yan (DY) production off various nuclear targets [3]; as well as the differential cross-sections and asymmetries of the W ± and Z boson production in p+Pb collisions at the LHC [6].…”

Nuclear parton distributions

“…This analysis suggests a common off-shell function for the quark and antiquark distributions, independent of Q 2 and the parton type. This observation is supported by a recent QCD global analysis of proton and deuteron data [36], as well as by the studies of the nuclear DY production of muon pair in Sec.3 and the W/Z boson production in p+Pb collisions in Sec.4.…”

Precision measurements of fundamental interactions with (anti)neutrinos

“…Examples are given by precision tests of the Adler [17] and Gross-Llewellyn Smith [18] sum rules on hydrogen and in nuclei [21,22]. Similarly, by exploiting the isospin symmetry F νn 2 = Fν p 2 on hydrogen, we can obtain a model-independent measurement of the free neutron structure functions, as well as a measurement of the large x behavior of the d/u quark ratio [19]. These measurements can also be used for precision tests of the isospin (charge) symmetry and would help to elucidate the flavor structure of the nucleon [20].…”