Pumping option for ultra-cold neutron sources

A new shutter operation for advanced ultra-cold neutron (UCN) sources at pulsed spallation sources is proposed which results in a remarkable intensity gain. It uses the pulse structure of the source and fills the storage vessel up to a density related to the peak intensity of the source and not only to the average intensity. For the AUSTRON neutron spallation project this results in UCN densities up to 105 cm−3 which is about 3–4 orders of magnitudes larger than that of existing sources.