Negative Energy Neutron Resonance inCl35

Abstract
The neutron scattering cross section of chlorine has been measured at various energies in the range from 0 to 3000 ev. These data have been fitted to a one-level Breit-Wigner scattering formula. A single real level (i.e., one of negative energy with respect to binding) in Cl36 at -75 ev is sufficient to account for the observed slow neutron properties of chlorine.