  The MAJORANA Collaboration is constructing the MAJORANA Demonstrator, an
ultra-low background, 44-kg modular high-purity Ge (HPGe) detector array to
search for neutrinoless double-beta decay in Ge-76. The phenomenon of surface
micro-discharge induced by high-voltage has been studied in the context of the
MAJORANA Demonstrator. This effect can damage the front-end electronics or
mimic detector signals. To ensure the correct performance, every high-voltage
cable and feedthrough must be capable of supplying HPGe detector operating
voltages as high as 5 kV without exhibiting discharge. R&D measurements were
carried out to understand the testing system and determine the optimum design
configuration of the high-voltage path, including different improvements of the
cable layout and feedthrough flange model selection. Every cable and
feedthrough to be used at the MAJORANA Demonstrator was characterized and the
micro-discharge effects during the MAJORANA Demonstrator commissioning phase
were studied. A stable configuration has been achieved, and the cables and
connectors can supply HPGe detector operating voltages without exhibiting
discharge.

Instrumentation and Detectors;High Energy Physics - Experiment;Nuclear Experiment