We report measurements of the charged daughter fraction of 218Po as a result of the 222Rn alpha decay, and the mobility of 218Po+ ions, using radon-polonium coincidences from the 238U chain identified in 532 live-days of DarkSide-50 WIMP-search data. The fraction of 218Po that is charged is found to be 0.37 ± 0.03 and the mobility of 218Po+ is (8.6 ± 0.1) × 10−4 cm Vs2.
Agnes, P., Albuquerque, I., Alexander, T., Alton, A., Ave, M., Back, H., et al. (2019). Measurement of the ion fraction and mobility of 218Po produced in 222Rn decays in liquid argon. JOURNAL OF INSTRUMENTATION, 4(11) [10.1088/1748-0221/14/11/P11018].