A novel apparatus for the investigation of material properties for the storage of ultracold neutrons

We have built a novel apparatus for the investigation of materials for the storage of ultracold neutrons. Neutrons are filled into a storage volume, confined at the bottom by a magnetic field, at the top by gravity and at the sides by the slit-less sample surface under investigation. For different beryllium and diamond-like carbon samples, storage times up to 200 s were obtained at room temperature. The corresponding loss parameters η for ultracold neutrons varied between 4.2 and 6.8×10-4 per wall collision.