Estimating cosmogenic backgrounds in nEXO at SNOLAB using Geant4 and FLUKA

@misc{ross2026estimating,
  title = {{Estimating cosmogenic backgrounds in nEXO at SNOLAB using Geant4 and FLUKA}},
  author = {R. Ross and S. Al Kharusi and T. Brunner and S. Sangiorgio and E. Caden and U. Wichoski and B. G. Lenardo and B. Mong and A. Odian and A. Piepke and S. Thibado and A. Pocar and R. Saldanha and L. J. Kaufman and E. A. Allen and A. Amy and I. J. Arnquist and A. Atencio and V. Belov and A. Bolotnikov and J. Breslin and P. A. Breur and J. Brodsky and E. Brown and E. van Bruggen and B. Burnell and D. Cesmecioglu and M. Chiu and R. Collister and E. Coulthard and T. Daniels and L. Darroch and X. Defay and R. DeVoe and Y. Ding and M. J. Dolinski and B. Eckert and A. Emara and W. Fairbank and J. Farine and B. T. Foust and D. Gallacher and N. Gallice and A. Gaur and W. Gillis and F. Girard and R. Gornea and G. Gratta and C. A. Hardy and J. Hasi and M. Heffner and E. Hein and J. D. Holt and A. Iverson and T. V. John and A. K. Karelin and D. K. Keblbeck and P. Knauss and A. Kuchenkov and K. S. Kumar},
  howpublished = {arXiv},
  year = {2026},
  month = nov,
  doi = {10.48550/arxiv.2611.00529},
  eprint = {2611.00529},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2611.00529},
  note = {CC BY-NC-SA 4.0},
}

TY  - UNPB
TI  - Estimating cosmogenic backgrounds in nEXO at SNOLAB using Geant4 and FLUKA
AU  - R. Ross
AU  - S. Al Kharusi
AU  - T. Brunner
AU  - S. Sangiorgio
AU  - E. Caden
AU  - U. Wichoski
AU  - B. G. Lenardo
AU  - B. Mong
AU  - A. Odian
AU  - A. Piepke
AU  - S. Thibado
AU  - A. Pocar
AU  - R. Saldanha
AU  - L. J. Kaufman
AU  - E. A. Allen
AU  - A. Amy
AU  - I. J. Arnquist
AU  - A. Atencio
AU  - V. Belov
AU  - A. Bolotnikov
AU  - J. Breslin
AU  - P. A. Breur
AU  - J. Brodsky
AU  - E. Brown
AU  - E. van Bruggen
AU  - B. Burnell
AU  - D. Cesmecioglu
AU  - M. Chiu
AU  - R. Collister
AU  - E. Coulthard
AU  - T. Daniels
AU  - L. Darroch
AU  - X. Defay
AU  - R. DeVoe
AU  - Y. Ding
AU  - M. J. Dolinski
AU  - B. Eckert
AU  - A. Emara
AU  - W. Fairbank
AU  - J. Farine
AU  - B. T. Foust
AU  - D. Gallacher
AU  - N. Gallice
AU  - A. Gaur
AU  - W. Gillis
AU  - F. Girard
AU  - R. Gornea
AU  - G. Gratta
AU  - C. A. Hardy
AU  - J. Hasi
AU  - M. Heffner
AU  - E. Hein
AU  - J. D. Holt
AU  - A. Iverson
AU  - T. V. John
AU  - A. K. Karelin
AU  - D. K. Keblbeck
AU  - P. Knauss
AU  - A. Kuchenkov
AU  - K. S. Kumar
PY  - 2026
DA  - 2026/11/01
PB  - arXiv
DO  - 10.48550/arxiv.2611.00529
UR  - https://arxiv.org/abs/2611.00529
AB  - The nEXO experiment was designed to search for neutrinoless double beta decay in the isotope ^136Xe, using a five-tonne, isotopically-enriched liquid xenon time projection chamber (TPC). To meet nEXO's sensitivity goal, significant effort is placed on background mitigation strategies. Here, we evaluate the expected cosmogenic background rate for nEXO if placed at its preferred underground host site, SNOLAB. A comparison of results from Geant4 and FLUKA Monte Carlo simulations are presented. We perform detailed Monte Carlo simulations of muons reaching the underground SNOLAB environment using both Geant4 and FLUKA to study the production of radioactive isotopes from both direct spallation reactions or subsequent neutron-induced reactions. We find that, of the isotopes produced, the only one of concern for nEXO is ^137Xe, produced by neutron capture on the xenon target. We develop a veto strategy that achieves an anticipated 92\% \xe{137} rejection efficiency while keeping dead time to less than 1 day over a 10 year exposure.
ER  -