2025/09/17 by M. B. Barbaro, Barbaro, M. B., Valerio Belocchi +5
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Neutrino Physics Research #Nuclear Theory (nucl-th) #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2509.13915
openalex publication_date 2025/09/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Meson-exchange currents (MEC) play a crucial role in the nuclear response to a leptonic probe, inducing the emission of two nucleons, the so-called 2p2h excitations. Here we report the results of our recent work \citeBelocchi:2025eix, in which we evaluated the 2p2h contribution to the (νμ,μ-p) neutrino cross section off a carbon target, which involves the simultaneous detection the outgoing muon and a proton in the final state. This process has recently been measured in long-baseline neutrino experiments, but no truly microscopic calculation for the 2p2h channel existed to be compared with these data until now. The calculation employs fully relativistic two-body currents and is carried out within the Relativistic Fermi Gas framework. It provides a generalization to the weak sector of the electromagnetic inclusive model developed in Ref.~\citeDePace:2003spn and an extension of the calculation to enable semi-inclusive predictions. A selection of our results for the semi-inclusive cross section versus the emitted proton variables is presented, both at fixed neutrino energy and folded with the T2K muon-neutrino flux.