1. Sensitivity of the NEXT experiment to Xe-124 double electron capture
- Author
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C.M.B. Monteiro, J.F.C.A. Veloso, G. Díaz, E.D.C. Freitas, B. Palmeiro, Y. Rodriguez Garcia, R. Weiss-Babai, J. Muñoz Vidal, F.P. Santos, Saunab Ghosh, Sandra K. Johnston, J.T. White, F. Ballester, J. Renner, Lior Arazi, J. Generowicz, A.B. Redwine, P. Herrero, V. Herrero, G. Martínez-Lema, J.M. Benlloch-Rodríguez, Paola Ferrario, A. Goldschmidt, J. Hauptman, L. Ripoll, B. J. P. Jones, J. S. Díaz, M. Martínez-Vara, P. Novella, F. Monrabal, J. Martín-Albo, J.J. Gómez-Cadenas, I.J. Arnquist, N. López-March, C.D.R. Azevedo, Kevin Bailey, A.D. McDonald, C. Adams, N. Byrnes, J. Torrent, Jose Repond, M. Kekic, S. Riordan, E. Church, R.D.P. Mano, T. Contreras, M. Querol, Javier Pérez, J.V. Carrión, C. Romo-Luque, L.M.P. Fernandes, B. Romeo, C. Sofka, C.A.O. Henriques, F.J. Mora, J.A. Hernando Morata, K. Woodruff, Jose A. Rodriguez, D. González-Díaz, L. Rogers, A. Usón, Marta Losada, C.A.N. Conde, Luis Labarga, T.M. Stiegler, A. Para, Víctor H. Alvarez, D. R. Nygren, F.I.G.M. Borges, A. Laing, J. Haefner, A. Simón, N. Yahlali, M. Sorel, A.F.M. Fernandes, P. Lebrun, S. Cebrián, Ana Martínez, A.L. Ferreira, Romain Esteve, R. C. Webb, M. Diesburg, R. Guenette, J. Escada, J.F. Toledo, S. Cárcel, K. Hafidi, J.M.F. dos Santos, Y. Ifergan, R. Felkai, Roberto Gutiérrez, and UAM. Departamento de Física Teórica
- Subjects
Nuclear and High Energy Physics ,Physics - Instrumentation and Detectors ,Electron capture ,Dark Matter and Double Beta Decay ,Extrapolation ,FOS: Physical sciences ,chemistry.chemical_element ,Electrons ,Electron ,01 natural sciences ,7. Clean energy ,Atomic ,High Energy Physics - Experiment ,TECNOLOGIA ELECTRONICA ,Nuclear physics ,High Energy Physics - Experiment (hep-ex) ,Xenon ,Particle and Plasma Physics ,Double beta decay ,0103 physical sciences ,Nuclear Matrix ,Nuclear ,Sensitivity (control systems) ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Nuclear Experiment ,Mathematical Physics ,Physics ,Quantum Physics ,Isotope ,010308 nuclear & particles physics ,Raigs beta -- Desintegració ,Detector ,Física ,Molecular ,Detectors ,Instrumentation and Detectors (physics.ins-det) ,Beta Decay ,Nuclear & Particles Physics ,chemistry ,13. Climate action ,Beta rays -- Decay - Abstract
[EN] Double electron capture by proton-rich nuclei is a second-order nuclear process analogous to double beta decay. Despite their similarities, the decay signature is quite di erent, potentially providing a new channel to measure the hypothesized neutrinoless mode of these decays. The Standard-Model-allowed two-neutrino double electron capture has been predicted for a number of isotopes, but only observed in 78Kr, 130Ba and, recently, 124Xe. The sensitivity to this decay establishes a benchmark for the ultimate experimental goal, namely the potential to discover also the lepton-number-violating neutrinoless version of this process. Here we report on the current sensitivity of the NEXT-White detector to 124Xe 2 ECEC and on the extrapolation to NEXT-100. Using simulated data for the 2 ECEC signal and real data from NEXT-White operated with 124Xe-depleted gas as background, we de ne an optimal event selection that maximizes the NEXT-White sensitivity. We estimate that, for NEXT-100 operated with xenon gas isotopically enriched with 1 kg of 124Xe and for a 5-year run, a sensitivity to the two-neutroni double electron capture half-life of 6x10exp22 years (at 90% con dence level) or better can be reached., The NEXT collaboration acknowledges support from the following agencies and institutions: the European Research Council (ERC) under the Advanced Grant 339787-NEXT; the European Union's Framework Programme for Research and Innovation Horizon 2020 (2014-2020) under the Marie Sklodowska-Curie Grant Agreements No. 674896, 690575 and 740055; the Ministerio de Economia y Competitividad and the Ministerio de Ciencia, Innovacion y Universidades of Spain under grants FIS2014-53371-C04, RTI2018-095979, the Severo Ochoa Program grants SEV-2014-0398 and CEX2018-000867-S, and the Maria de Maeztu Program MDM-2016-0692; the GVA of Spain under grants PROMETEO/2016/120 and SEJI/2017/011; the Portuguese FCT under project PTDC/FIS-NUC/2525/2014, under project UID/FIS/04559/2013 to fund the activities of LIBPhys, and under grants PD/BD/105921/2014, SFRH/BPD/109180/2015 and SFRH/BPD/76842/2011; the U.S. Department of Energy under contracts number DE-AC02-06CH11357 (Argonne National Laboratory), DE-AC02-07CH11359 (Fermi National Accelerator Laboratory), DE-FG02-13ER42020 (Texas A&M) and DE-SC0019223/DE-SC0019054 (University of Texas at Arlington); and the University of Texas at Arlington. DGD acknowledges Ramon y Cajal program (Spain) under contract number RYC-2015-18820. We also warmly acknowledge the Laboratori Nazionali del Gran Sasso (LNGS) and the Dark Side collaboration for their help with TPB coating of various parts of the NEXT-White TPC. Finally, we are grateful to the Laboratorio Subterraneo de Canfranc for hosting and supporting the NEXT experiment
- Published
- 2021