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Online $^{222}$Rn removal by cryogenic distillation in the XENON100 experiment

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 نشر من قبل Michael Murra
 تاريخ النشر 2017
  مجال البحث فيزياء
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We describe the purification of xenon from traces of the radioactive noble gas radon using a cryogenic distillation column. The distillation column is integrated into the gas purification loop of the XENON100 detector for online radon removal. This enabled us to significantly reduce the constant $^{222}$Rn background originating from radon emanation. After inserting an auxiliary $^{222}$Rn emanation source in the gas loop, we determined a radon reduction factor of R > 27 (95% C.L.) for the distillation column by monitoring the $^{222}$Rn activity concentration inside the XENON100 detector.



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