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تسجيل مستخدم جديدSpin flip loss in magnetic confinement of ultracold neutrons for neutron lifetime experiments
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We analyze the spin flip loss for ultracold neutrons in magnetic bottles of the type used in experiments aiming at a precise measurement of the neutron lifetime, extending the one-dimensional field model used previously by Steyerl $textit{et al.}$ [Phys.Rev.C $mathbf{86}$, 065501 (2012)] to two dimensions for cylindrical multipole fields. We also develop a general analysis applicable to three dimensions. Here we apply it to multipole fields and to the bowl-type field configuration used for the Los Alamos UCN$tau$ experiment. In all cases considered the spin flip loss calculated exceeds the Majorana estimate by many orders of magnitude but can be suppressed sufficiently by applying a holding field of appropriate magnitude to allow high-precision neutron lifetime measurements, provided other possible sources of systematic error are under control.
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