Storage of ultracold neutrons in a vessel long enough for β decay
Kosvintsev Yu. Yu. , Morozov V. I. , Terekhov G. I.
Cooling a hermetically sealed aluminum vessel to 80 К lowers the probability for the loss of ultracold neutrons to a level near the theoretical level. The additional loss in aluminum vessels is shown to be caused by a heating of the ultracold neutrons, for which the probability depends strongly on the temperature. A "clean" vessel in which ultracold neutrons can be stored for a time equal to their lifetime with respect to β decay can be produced by freezing heavy ice on the surface of an aluminum vessel.