Theoretical predictions for extraction of G n E from semi - inclusive electron scattering on polarized 3 He based on various nucleon - nucleon interactions

The process − − → 3 He(e, e ′ n) is theoretically analyzed with the aim to search for sensitivity to the electric form factor of the neutron, G n E. Faddeev calculations based on five high precision nucleon-nucleon force models are employed and stability versus exchange of the nucleon-nucleon forces is demonstrated. 1 In a recent paper [1] we investigated the sensitivity of the process − − → 3 He(e, e ′ n) to the extraction of the electric form factor of the neutron. That study was based on the AV18 [2] nucleon-nucleon (NN) force and related MEC's and Faddeev calculations for 3 He consistent with the final state continuum. We found that final state interaction (FSI) effects were quite important and an analysis without FSI cannot be recommended. Though we know from most of our experience that the theoretical results are quite stable under exchange of one of the high precision NN potentials by another one, we would like to supplement our previous paper [1] by explicitely demonstrating the independence from the NN interaction for that specific process. We refer to [1] for all information about the formalism and the definitions of the asymmetries A ⊥ and A. Since in contrast to AV18 there are no consistent MEC's worked out for the other four high precision NN potentials CD Bonn [3], Nijmegen 93, Nijmegen I and II [4] we show only the asymmetries evaluated with those NN potentials based on the standard nonrelativistic single nucleon current operator. The important ratio A ⊥ /A for the extraction of G n E is displayed in Fig. 1 for the same q 2-values as in [1]. This figure corresponds to Fig. 8 of Ref. [1]. It shows the five predictions (including AV18) for a fixed choice of G n E as used in [1]. In order to provide the necessary information on the sensitivity with respect to G n E we include also three additional curves, where G n E is multiplied by 0.75, 1.25 and 1, respectively and this for the choice of AV18+MEC. These additional three curves are the same as in Fig. 8 of Ref. [1]. We see first of all in all cases a rather narrow spread of the five NN force predictions which document the expected stability of the results under exchange of one NN force by another one. However, we had to reduce somewhat the …