Going to the limit of NSE

Neutron spin echo (NSE) is characterized by a broad variety of new developments. The obvious trend is towards the highest possible energy resolution at the highest possible wavelengths by further developing the generic IN11 design. The planned NSE spectrometer at the SNS will further push the limits of NSE reaching Fourier times as long as 1 ms. On the other hand, simultaneous measurements over higher total solid angles require the real cylindrical symmetry of the magnetic field configuration realized with the spectrometer SPAN at BENSC. The state-of-the-art neutron optical elements lead to considerable gains in neutron flux and allow for extending the wavelength range upto very high wavelengths as well as down to the thermal spectrum. With thermal neutrons NSE reaches energy transfers, which up to now were reserved to TOF spectroscopy, while keeping the advantage of the most straightforward data analysis combine with the most wide dynamic range also in the sub-picosecond Fourier time range. This is illustrated by a detailed analysis of both the alpha and beta processes of glass forming polymers close to the glass transition.