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arXiv · 2304.04622

PVEMC: Isolating the flavor-dependent EMC effect using parity-violating inelastic scattering in SoLID

Abstract

In order to better understand the EMC effect, we propose a clean and precise measurement of the flavor dependence of the EMC effect using parity-violating deep inelastic scattering on a $^{48}$Ca target. This measurement will provide an extremely sensitive test for flavor dependence in the modification of nuclear parton distribution functions (PDFs) for neutron-rich nuclei. A measurement of the flavor dependence will provide new and vital information and help to explain nucleon modification at the quark level. In addition to helping understand the origin of the EMC effect, a flavor-dependent nuclear pdf modification could significantly impact a range of processes, including neutrino-nucleus scattering, nuclear Drell-Yan processes, and e-A observables at the Electron-Ion Collider. The parity-violating asymmetry APV from $^{48}$Ca using an 11 GeV beam at $80\ μA$ will be measured using the SoLID detector in its PVDIS configuration. In 68 days of data taking, we will reach $0.7-1.3\%$ statistical precision for $0.2<x<0.7$ with $0.6-0.7\% $ systematic uncertainties. The goal is to make the first direct measurement of the flavor dependence of the EMC effect. The precision of the measurement will allow for quantification of the flavor-dependent effects, greatly improving our ability to differentiate between models of the EMC effect and constraining the u- and d-quark contributions in neutron rich nuclei.

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Rakitha Beminiwattha, John Arrington, David J. Gaskell. 2023-09-26. PVEMC: Isolating the flavor-dependent EMC effect using parity-violating inelastic scattering in SoLID. https://arxiv.org/abs/2304.04622

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