Speaker
Description
We compute the contribution of meson-exchange currents (MEC) to the one-particle
emission transverse response of nuclear matter, including short-range correlations (SRC)
within the independent pair approximation. Our results show a significant enhancement
of the transverse response in electron scattering, in contrast to independent-particle
models that neglect SRC [1]. SRC are incorporated by solving the Bethe-Goldstone
(BG) equation in the nuclear medium [2] using the Granada-2013 NN potential. This
realistic interaction, fitted to the world database of NN scattering [3], allows the BG
equation to be reduced to a system of linear equations, which can be solved exactly.
The nucleon-pair wave function acquires high-momentum components, as Pauli block-
ing prevents low-momentum scattering in the nuclear medium. In one-particle emis-
sion reactions, the MEC 1p1h matrix element interferes with the one-body current
contribution, modifying the response function. When the MEC operator acts on the
high-momentum components of the correlated wave function, it generates an addi-
tional contribution that enhances the response beyond the uncorrelated Fermi gas. This
enhancement is consistent with Fabrocini’s results [4], within correlated basis function
perturbation theory and provides a step toward explaining experimental data on the
transverse response.
We extend the formalism to the weak sector relevant for quasielastic neutrino scat-
tering, which is of particular interest in neutrino oscillation experiments. The MEC–one-
body interference response in nuclear matter includes a contribution from the pure
Fermi gas and another from the coupling to high-momentum components generated by
short-range correlations between nucleon pairs. These results are presented here for the
first time in the case of neutrino-induced reactions where the differents contributions
to the response functions are analyzed in detailed for different kinematics.
[1] P. R. Casale, J. E. Amaro, V. Belocchi, M. B. Barbaro, A. De Pace and M. Martini,
[arXiv:2503.08391 [nucl-th]].
[2] P. R. Casale, J. E. Amaro, E. Ruiz Arriola and I. Ruiz Simo, Phys. Rev. C 108,
no.5, 054001 (2023)
[3] R. Navarro Pérez, J. E. Amaro and E. Ruiz Arriola, Phys. Rev. C 88, no.6, 064002
(2013) [erratum: Phys. Rev. C 91, no.2, 029901 (2015)]
[4] Adelchi Fabrocini, Phys. Rev. C 55 (1997) 338.
