Superconducting UCN Polarizer for a New EDM Spectrometer
A test experiment has shown that the number of ultracold neutrons (UCN) of one polarization state, transmitted through a 100 μm Al foil when placed in a 5 T magnetic field, is greater by 3.8 times. The increased transmission is due to the higher velocity of the UCN passing through the foil.
Depolarization of ultracold neutrons during their storage in material bottles
The depolarization of ultracold neutrons (UCN) during their storage in traps has been investigated. The neutron spin-flip probability for the materials studied amounts to ∼ (1–2) × 10 −5 per collision and does not depend on the temperature. The possible connection between the phenomenon of UCN depolarization and that of anomalous losses is discussed.  2003 Published by Elsevier Science B.V.
Ultra cold neutron life times in glow discharge cleaned bottles
Life times of ultra cold neutrons in tubes made of various materials have been increased with improvement of surface cleanliness. With glow discharge cleaning in vacua of only 10−4–10−3 torr, life times for long storage periods were obtained that differ by less than a factor of 2 from calculated values in the case of stainless steel and aluminium and by a factor of 3 for quartz. Surface recontamination is slow at the achieved level and approaches a stable value well below that before cleaning. A temperature dependence of ultra cold neutron reflection loss rates was observed. A direct correlation between reflection losses and the surface hydrogen concentration was established. We conclude that for smooth surfaces of materials with low reaction cross section, losses are mainly caused by upscattering on tightly bound hydrogen. The probability is discussed that the remaining losses are due to still incomplete cleanliness of the surface caused by hydrogen recontamination from the bulk and the atmosphere.