Cross Section Measurements of Deuteron Electro-Disintegration at Very High Recoil Momenta and Large 4-Momentum Transfers ($Q^{2}$)

TL;DR

This study measures deuteron electro-disintegration cross sections at high recoil momenta and large momentum transfers, providing new data that tests theoretical models and reveals discrepancies at high recoil momenta.

Contribution

It provides new experimental data at high recoil momenta and large $Q^2$, extending previous measurements and challenging existing theoretical calculations.

Findings

Data agree with previous measurements up to 550 MeV/c recoil momentum.

At certain angles, PWIA dominates, indicating suppressed FSI, MEC, and IC effects.

Significant disagreement with theory for recoil momenta above 700 MeV/c.

Abstract

The $^{2}$H$(e,e'p)n$ cross sections have been measured at negative 4-momentum transfers of $Q^{2} = 4.5\pm0.5$ (GeV/c)$^{2}$ and $Q^{2} = 3.5\pm0.5$ (GeV/c)$^{2}$ reaching neutron recoil (missing) momenta up to $p_{\mathrm{r}}\sim$1.0 GeV/c. The data have been obtained at fixed neutron recoil angles $5^{\circ}\leq\theta_{nq}\leq95^{\circ}$ with respect to the 3-momentum transfer $\vec{q}$. The new data agree well with the previous data which reached $p_{\mathrm{r}}\sim550$ MeV/c. At $\theta_{nq}=35^{\circ}$ and $45^{\circ}$, final state interactions (FSI), meson exchange currents (MEC) and isobar configurations (IC) are suppressed and the plane wave impulse approximation (PWIA) provides the dominant cross section contribution. The new data are compared to recent theoretical calculations, and a significant disagreement for recoil momenta $p_{\mathrm{r}}>700$ MeV/c is observed.