A relativistic single particle model is used to calculate the inclusive $(e,e')$ reaction from $A=$12, 40, 56, 197, and 208 nuclei in the quasielastic region. We have shown that this model provides a very good description of the available experimental cross sections when they are dominated by the quasielastic process. In this paper we use this model to investigate the dependence of $y$-scaling on electron kinematics, particularly the electron scattering angle, for a range of squared four momentum transfer $0.20-0.80$ (GeV/c)$^2$. In this kinematic domain, Coulomb distortion of the electron does not significantly affect scaling, but final state interactions of the knocked out nucleon do affect scaling particularly when the nucleons have lower energies. In general, we find that scaling works for this reaction, but at lower values of the four momentum transfer, the scaling function does have some dependence on the electron scattering angle. We also consider a modification of y-scaling to include small binding energy effects as a function of Z and A and show that there is some improvement in scaling.
Microscopics of meson degrees of freedom in nucleons and mesons in nuclei - what can be seen in the process of quasielastic knockout of mesons by high-energy electrons
Our model, based on Quantum Chromodynamics, emphasizes the role of triton clustering in nuclei. As there is good empirical support of triton clustering in nuclei, we may even treat this as a good phenomenological working hypothesis as well. Here we show how our model finds remarkable success in being able to provide a consistent and interconnected understanding of such diverse empirical realities as the missing electric-charge in quasielastic electron scattering, and simultaneously, also the puzzling data within the studies of exotic nuclei. This gives us confidence, that our model should be t…
We develop an asymmetric relativistic Fermi gas model for the study of the electroweak nuclear response in the quasielastic region. The model takes into account the differences between neutron and proton densities in asymmetric (N > Z) nuclei, as well as differences in the neutron and proton separation energies. We present numerical results for both neutral and charged current processes, focusing on nuclei of interest for ongoing and future neutrino oscillation experiments. We point out some important differences with respect to the commonly employed symmetric Fermi gas model.
Understanding quasielastic electron- and neutrino-scattering from nuclei has taken on new urgency with current and planned neutrino oscillation experiments, and with electron scattering experiments measuring specific final states, such as those involving nucleon pairs in ``back-to-back'' configurations. Accurate many-body methods are available for calculating the response of light ($A \leq 12$) nuclei to electromagnetic and weak probes, but they are computationally intensive and only applicable to the inclusive response. In the present work we introduce a novel approach, based on realistic mod…
A detailed study of the electromagnetic responses for quasielastic $(e,e')$ reactions from nuclear matter is presented within the framework of a relativistic model including momentum dependent scalar and vector mean field potentials in both the initial and final nucleon wave function states. The effects ascribed to the use of energy-dependent potentials are carefully analyzed by comparing their predictions with the responses obtained in the case of constant, i.e., energy-independent, potentials, as well as with the plane wave limit in the final state. The study is extended to the scaling pheno…
The article of Pastore et al, while proposing an interesting and potentially useful approach for the generalisation of Quantum Monte Carlo techniques to the treatment of the nuclear electromagnetic response, features an incorrect and misleading discussion of y-scaling. The response to interactions with transversely polarised virtual photons receives sizeable contributions from non-scaling processes, in which the momentum transfer is shared between two nucleons. It follows that, contrary to what is stated by the the authors, y-scaling in the transverse channel is accidental.
A microscopic analysis of the optical potentials (OPs) and cross sections of quasielastic scattering of $^{12,14}$Be on $^{12}$C at 56 MeV/nucleon and on protons at energy near 700 MeV is carried out. For lower energy scattering the real part of the OP is calculated by using of double-folding procedure accounting for the anti-symmetrization effects, while the imaginary part is obtained on the base of the high-energy approximation (HEA). The HEA is also applied to the calculations of both real and imaginary OPs when solving the relativistic equation for the high-energy proton-nucleus elastic sc…
We use a recent scaling analysis of the quasielastic electron scattering data from $^{12}$C to predict the quasielastic charge-changing neutrino scattering cross sections within an uncertainty band. We use a scaling function extracted from a selection of the $(e,e')$ cross section data, and an effective nucleon mass inspired by the relativistic mean-field model of nuclear matter. The corresponding super-scaling analysis with relativistic effective mass (SuSAM*) describes a large amount of the electron data lying inside a phenomenological quasielastic band. The effective mass incorporates the e…
We perform a combined analysis of inclusive electron scattering data from $A=3$ nuclei in the deep-inelastic and quasielastic scattering regions, using Monte Carlo analysis methods and the nuclear weak binding approximation to establish the range over which the data can be described within the same theoretical framework. Comparison with quasielastic $^3$He cross sections from SLAC and Jefferson Lab suggests that most features of the $x \gtrsim 1$ data can be reasonably well described in the impulse approximation with finite-$Q^2$ nuclear smearing functions for momentum transfers $Q^2 \gtrsim 1…
Polarization transfer observables for quasielastic proton-nucleus scattering in terms of a complete Lorentz invariant representation of the NN scattering matrix
We briefly review the concept of scaling and how it occurs in quasielastic electron and neutrino scattering from nuclei, and then the particular approach to scaling in the short-time approximation. We show that, while two-nucleon currents do significantly enhance the transverse electromagnetic response, they do not spoil scaling, but in fact enhance it. We provide scaling results obtained in the short-time approximation that verify this claim. The enhanced scaling is not ``accidental'' -- as claimed in Ref.~\cite{Benhar:2020jye} -- but rather reflects the dominant role played by pion exchange …
