The application of neutron spin echo on pulsed neutron sources

In the neutron-spin-echo technique a comparison is made between the before and after scattering times-of-flight for each neutron. On a pulsed source the most readily available quantity is the total time from neutron pulse to detection, i.e. the sum of the times-of-flight from source to sample and from sample to detector. These two items of information can be very naturally combined for high resolution inelastic spectrometry. The principle of such a spectrometer for μeV resolution is described. It is shown that the neutron-spin-echo method on a pulsed source makes it possible to utilize a large band of the wavelength spectrum at the same time, thus providing a substantial (up to 1000-fold) gain in neutron economy as compared to the classical methods of comparable resolution. (orig.)