Measurement of the EMC Effect in the Deuteron

TL;DR

This study measures the EMC effect in deuterons using recent data, revealing deviations from unity consistent with nuclear physics models and short-range correlations, across a specific kinematic range.

Contribution

First measurement of the EMC effect in deuterons using BONuS data, confirming theoretical models and correlations with short-range nucleon interactions.

Findings

The EMC ratio in deuterons deviates from unity with a negative slope.

Results align with models including off-shell corrections.

Findings support the link between EMC effect and nucleon-nucleon correlations.

Abstract

We have determined the structure function ratio $R^d_{\rm EMC}=F_2^d/(F_2^n+F_2^p)$ from recently published $F_2^n/F_2^d$ data taken by the BONuS experiment using CLAS at Jefferson Lab. This ratio deviates from unity, with a slope $dR_{\rm EMC}^{d}/dx= -0.10\pm 0.05$ in the range of Bjorken $x$ from 0.35 to 0.7, for invariant mass $W>1.4$ GeV and $Q^2>1$ GeV$^2$. The observed EMC effect for these kinematics is consistent with conventional nuclear physics models that include off-shell corrections, as well as with empirical analyses that find the EMC effect proportional to the probability of short-range nucleon-nucleon correlations.