The diverse measured data base of n+^{237}Np is evaluated using a generalized least squares code and statistical theory of nuclear reactions. Consistent description of the total, fission and partial inelastic scattering data in 1  3 MeV energy range provides an important constraint for the absorption cross section. Important constraints for the measured capture cross section come from the average radiation S0 and S1 strength functions. An abrupt change of the inelastic data shape at En ¡ 1.5 MeV is explained by the sharp increase of the level density of the residual oddeven nuclide ^{237}Np due to the onset of threequasiparticle excitations. The in fluence of exclusive (n, xnf) prefission neutrons on prompt fission neutron spectra and (n, xn) reactions spectra is modeled. Contributions of emissive/nonemissive fission and exclusive spectra of (n, xnf) reactions are defined by a consistent description of the ^{237}Np(n, F), ^{237}Np (n, 2n)^{236s}Np reactions and the ratio of the yields of shortlived isomer (1^{}) and longlived ground (6^{}) ^{236}Np states measured at ¡14 MeV. The isomer ratio of the yields of shortlived ground (1^{}) ^{242g}Am and longlived isomer (5^{}) ^{242m}Am states in ^{243}Am(n, 2n) reaction is calculated modeling the gammadecay of the possible GallaherMoshkowski doublet states of ^{242}Am.
