# Online $^{222}$Rn removal by cryogenic distillation in the XENON100 experiment **Authors:** XENON Collaboration: E. Aprile, J. Aalbers, F. Agostini, M. Alfonsi,, F. D. Amaro, M. Anthony, F. Arneodo, P. Barrow, L. Baudis, B. Bauermeister,, M. L. Benabderrahmane, T. Berger, P. A. Breur, A. Brown, E. Brown, S., Bruenner, G. Bruno, R. Budnik, L. B\"utikofer, J. Calv\'en, J. M. R. Cardoso,, M. Cervantes, D. Cichon, D. Coderre, A. P. Colijn, J. Conrad, J. P., Cussonneau, M. P. Decowski, P. de Perio, P. Di Gangi, A. Di Giovanni, S., Diglio, E. Duchovni, G. Eurin, J. Fei, A. D. Ferella, A. Fieguth, D. Franco,, W. Fulgione, A. Gallo Rosso, M. Galloway, F. Gao, M. Garbini, C. Geis, L. W., Goetzke, L. Grandi, Z. Greene, C. Grignon, C. Hasterok, E. Hogenbirk, R., Itay, B. Kaminsky, G. Kessler, A. Kish, H. Landsman, R. F. Lang, D. Lellouch,, L. Levinson, M. Le Calloch, Q. Lin, S. Lindemann, M. Lindner, J. A. M. Lopes, A. Manfredini, I. Maris, T. Marrod\'an Undagoitia, J. Masbou, F. V. Massoli,, D. Masson, D. Mayani, Y. Meng, M. Messina, K. Micheneau, B. Miguez, A., Molinario, M. Murra, J. Naganoma, K. Ni, U. Oberlack, S. E. A. Orrigo, P., Pakarha, B. Pelssers, R. Persiani, F. Piastra, J. Pienaar, M.-C. Piro, V., Pizzella, G. Plante, N. Priel, L. Rauch, S. Reichard, C. Reuter, A. Rizzo, S., Rosendahl, N. Rupp, R. Saldanha, J. M. F. dos Santos, G. Sartorelli, M., Scheibelhut, S. Schindler, J. Schreiner, M. Schumann, L. Scotto Lavina, M., Selvi, P. Shagin, E. Shockley, M. Silva, H. Simgen, M. v. Sivers, A. Stein,, D. Thers, A. Tiseni, G. Trinchero, C. Tunnell, N. Upole, H. Wang, Y. Wei, C., Weinheimer, J. Wulf, J. Ye, Y. Zhang, and I. Cristescu arXiv: 1702.06942 ยท 2017-06-05 ## TL;DR This paper presents a cryogenic distillation method integrated into the XENON100 detector to effectively reduce radon-222 background, improving the detector's sensitivity for rare event searches. ## Contribution The study demonstrates the successful implementation of an online cryogenic distillation process for radon removal in a large-scale xenon detector, achieving a radon reduction factor of over 27. ## Key findings - Radon reduction factor R > 27 (95% C.L.) achieved - Cryogenic distillation effectively reduces radon background - Enhanced detector sensitivity for rare events ## Abstract 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. --- Source: https://tomesphere.com/paper/1702.06942