The Majorana Demonstrator searches for neutrinoless double-beta decay of$^{76}$Ge using arrays of high-purity germanium detectors. If observed, thisprocess would demonstrate that lepton number is not a conserved quantity innature, with implications for grand-unification and for explaining thepredominance of matter over antimatter in the universe. A problematicbackground in such large granular detector arrays is posed by alpha particles.In the Majorana Demonstrator, events have been observed that are consistentwith energy- degraded alphas originating on the passivated surface, leading toa potential background contribution in the region-of-interest for neutrinolessdouble-beta decay. However, it is also observed that when energy depositionoccurs very close to the passivated surface, charges drift through the bulkonto that surface, and then drift along it with greatly reduced mobility. Thisleads to both a reduced prompt signal and a measurable change in slope of thetail of a recorded pulse. In this contribution we discuss the characteristicsof these events and the development of a filter that can identify theoccurrence of this delayed charge recovery, allowing for the efficientrejection of passivated surface alpha events in analysis.
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