Experimental and theoretical aspects of high resolution neutron spectroscopy

In the paper recent developments in high-resolution neutron spectrometers are briefly reviewed. Particular consideration is given to fast neutron spectrometers which are used with isochronous cyclotrons. A few selected theoretical aspects of neutron spectroscopy are discussed. It is shown that the modern high-resolution spectrometers appear to be most useful to furthering the understanding of neutron resonance reactions. In particular the isochronous cyclotron spectrometers provide the high neutron intensity to perform high resolution total and partial cross-section measurements needed to investigate neutron resonance scattering proceeding through well defined spin states of high partial waves