2022/11/08 by Hana Gil, Gil, Hana, Chang Ho Hyun +3 · 1 citation
Physics and Astronomy · #FOS: Physical sciences #Nuclear Physics and Applications #Nuclear Theory (nucl-th) #Nuclear physics research studies #Scientific Research and Discoveries
paper · pdf · doi:10.48550/arxiv.2211.03948
openalex publication_date 2022/11/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Recent measurement of the parity-violating (PV) asymmetry in the elastic electron scattering on 27Al target evokes the interest in the distribution of the neutron in the nucleus. In this work, we calculate the neutron skin thickness (Rnp) of 27Al with nonrelativistic nuclear structure models. We focus on the role of the effective mass, symmetry energy and pairing force. Models are selected to have effective masses in the range (0.58-1.05)M where M is the nucleon mass in free space, and stiffness of the symmetry energy is varied by choosing the slope of the symmetry energy in the range 9.4 -- 100.5 MeV. Effect of pairing force is investigated by calculating Rnp with and without pairing, and using two different forms of the pairing force. With nine models, we obtain Rnp = 0.001 - 0.014 fm. The result is independent of the effective mass, symmetry energy, and the form of pairing force. However, Rnp is negative when the pairing force is switched off, so the pairing force plays an essential role to make Rnp positive and constrained in a narrow range. We also calculate the PV asymmetry (A\rm pv) in the elastic electron-27Al scattering in the Born approximation at the kinematics of the Qweak experiment. We obtain a very narrow-ranged result A\rm pv = (2.07 -- 2.09) × 10-6. The result is consistent with the experiment and insensitive to the effective mass, symmetry energy and pairing force.