A clean, bright, and versatile source of neutron decay products

Understand

We present a case study on a new type of cold neutron beam station for the investigation of angular correlations in the beta-decay of free neutrons.

• With this beam station, called PERC, the 'active decay volume' lies inside the neutron guide, and the charged neutron decay products are magnetically guided towards the end of the neutron guide.
• Hence, the guide delivers at its exit a beam of decay electrons and protons, under well-defined and precisely variable conditions, which can be well separated from the cold neutron beam.
• In this way a general-purpose source of neutron decay products is obtained which can be used for various different experiments in neutron decay correlation spectroscopy.