Density matrix of virtual nucleon in ν+d → N+N+μ reaction

Suggested is a formalism of the virtual nucleon density matrix which simplifies and unifies calculation of cross sections of inelastic scattering of particles on deuteron followed by spallation of the latter. The vector polarization of the initial deuteron may be unambiguously related to the virtual nucleon polarization. The formalism allows to take into account the deuteron binding energy effect and also such relativistic effects as the nucleon off-mass-shell effect and the antinucleon contribution. The efficiency of the density matrix method is demonstrated using the anti ν + d → μ+ + n + n reaction as an example. For this reaction the differential cross sections with μ+ and n detection in the final state and with only μ+ detection have been found