Abstract

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 different, potentially providing a new channel to measure the hypothesized neutrinoless mode of these decays. The Standard-Model-allowed two-neutrino double electron capture (2νEC EC) 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, 0νEC EC. Here we report on the current sensitivity of the NEXT-White detector to 124Xe 2νEC EC and on the extrapolation to NEXT-100. Using simulated data for the 2νEC EC signal and real data from NEXT-White operated with 124Xe-depleted gas as background, we define 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 2νEC EC half-life of 6 × 1022 y (at 90% confidence level) or better can be reached.

Details

Title
Sensitivity of the NEXT experiment to Xe-124 double electron capture
Author
Martínez-Lema, G 1   VIAFID ORCID Logo  ; Martínez-Vara, M 2 ; Sorel, M 3 ; Adams, C 4 ; Álvarez, V 5 ; Arazi, L 6 ; Arnquist, I J 7 ; Azevedo, C D, R 8 ; Bailey, K 4 ; Ballester, F 5 ; Benlloch-Rodríguez, J M 9 ; Borges F I G M 10 ; Byrnes, N 11 ; Cárcel, S 3 ; Carrión, J V 3 ; Cebrián, S 12 ; Church, E 7 ; Conde C A N 10 ; Contreras, T 13 ; Díaz, G 14 ; Díaz, J 3 ; Diesburg, M 15 ; Escada, J 10 ; Esteve, R 5 ; Felkai, R 16 ; Fernandes A F M 17 ; Fernandes L M P 17 ; Ferrario, P 18 ; Ferreira, A L 8 ; Freitas, E D, C 17 ; Generowicz, J 19 ; Ghosh, S 13 ; Goldschmidt, A 20 ; Gómez-Cadenas, J J 18 ; González-Díaz, D 14 ; Guenette, R 13 ; Gutiérrez, R M 21 ; Haefner, J 13 ; Hafidi, K 4 ; Hauptman, J 22 ; Henriques C A O 17 ; Hernando Morata J A 14 ; Herrero, P 19 ; Herrero, V 5 ; Ifergan, Y 23 ; Johnston, S 4 ; Jones B J P 11 ; Kekic, M 24 ; Labarga, L 25 ; Laing, A 11 ; Lebrun, P 15 ; López-March, N 26 ; Losada, M 21 ; Mano R D P 17 ; Martín-Albo, J 3 ; Martínez, A 2 ; McDonald, A D 11 ; Monrabal, F 18 ; Monteiro C M B 17 ; Mora, F J 5 ; Muñoz, Vidal J 2 ; Novella, P 3 ; Nygren, D R 11 ; Palmeiro, B 24 ; Para, A 15 ; Pérez, J 27 ; Querol, M 3 ; Redwine, A B 6 ; Renner, J 24 ; Repond, J 4 ; Riordan, S 4 ; Ripoll, L 28 ; Rodríguez, García Y 21 ; Rodríguez, J 5 ; Rogers, L 11 ; Romeo, B 29 ; Romo-Luque, C 3 ; Santos, F P 10 ; dos Santos J M F 17 ; Simón, A 6 ; Sofka, C 30 ; Stiegler, T 31 ; Toledo, J F 5 ; Torrent, J 19 ; Usón, A 3 ; Veloso J F C A 8 ; Webb, R 31 ; Weiss-Babai, R 6 ; White, J T 31 ; Woodruff, K 11 ; Yahlali, N 3 

1  Instituto de Física Corpuscular (IFIC), CSIC & Universitat de València, Paterna, Spain (GRID:grid.470047.0) (ISNI:0000 0001 2178 9889); Universidad de Santiago de Compostela, Instituto Gallego de Física de Altas Energías, Santiago de Compostela, Spain (GRID:grid.11794.3a) (ISNI:0000000109410645); Weizmann Institute of Science, Rehovot, Israel (GRID:grid.13992.30) (ISNI:0000 0004 0604 7563) 
2  Instituto de Física Corpuscular (IFIC), CSIC & Universitat de València, Paterna, Spain (GRID:grid.470047.0) (ISNI:0000 0001 2178 9889); Donostia International Physics Center (DIPC), Donostia-San Sebastian, Spain (GRID:grid.452382.a) (ISNI:0000 0004 1768 3100) 
3  Instituto de Física Corpuscular (IFIC), CSIC & Universitat de València, Paterna, Spain (GRID:grid.470047.0) (ISNI:0000 0001 2178 9889) 
4  Argonne National Laboratory, Argonne, U.S.A. (GRID:grid.187073.a) (ISNI:0000 0001 1939 4845) 
5  Universitat Politècnica de València, Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC, Valencia, Spain (GRID:grid.157927.f) (ISNI:0000 0004 1770 5832) 
6  Ben-Gurion University of the Negev, Nuclear Engineering Unit, Faculty of Engineering Sciences, Beer-Sheva, Israel (GRID:grid.7489.2) (ISNI:0000 0004 1937 0511) 
7  Pacific Northwest National Laboratory (PNNL), Richland, U.S.A. (GRID:grid.451303.0) (ISNI:0000 0001 2218 3491) 
8  Universidade de Aveiro, Institute of Nanostructures, Nanomodelling and Nanofabrication (i3N), Aveiro, Portugal (GRID:grid.7311.4) (ISNI:0000000123236065) 
9  Donostia International Physics Center (DIPC), Donostia-San Sebastian, Spain (GRID:grid.452382.a) (ISNI:0000 0004 1768 3100); Instituto de Física Corpuscular (IFIC), CSIC & Universitat de València, Paterna, Spain (GRID:grid.470047.0) (ISNI:0000 0001 2178 9889) 
10  University of Coimbra, LIP, Department of Physics, Coimbra, Portugal (GRID:grid.8051.c) (ISNI:0000 0000 9511 4342) 
11  University of Texas at Arlington, Department of Physics, Arlington, U.S.A. (GRID:grid.267315.4) (ISNI:0000 0001 2181 9515) 
12  Universidad de Zaragoza, Centro de Astropartículas y Física de Altas Energías (CAPA), Zaragoza, Spain (GRID:grid.11205.37) (ISNI:0000 0001 2152 8769) 
13  Harvard University, Department of Physics, Cambridge, U.S.A. (GRID:grid.38142.3c) (ISNI:000000041936754X) 
14  Universidad de Santiago de Compostela, Instituto Gallego de Física de Altas Energías, Santiago de Compostela, Spain (GRID:grid.11794.3a) (ISNI:0000000109410645) 
15  Fermi National Accelerator Laboratory, Batavia, U.S.A. (GRID:grid.417851.e) (ISNI:0000 0001 0675 0679) 
16  Ben-Gurion University of the Negev, Nuclear Engineering Unit, Faculty of Engineering Sciences, Beer-Sheva, Israel (GRID:grid.7489.2) (ISNI:0000 0004 1937 0511); Nuclear Research Center Negev, Beer-Sheva, Israel (GRID:grid.419373.b) (ISNI:0000 0001 2230 3545); Instituto de Física Corpuscular (IFIC), CSIC & Universitat de València, Paterna, Spain (GRID:grid.470047.0) (ISNI:0000 0001 2178 9889) 
17  University of Coimbra, LIBPhys, Physics Department, Coimbra, Portugal (GRID:grid.8051.c) (ISNI:0000 0000 9511 4342) 
18  Donostia International Physics Center (DIPC), Donostia-San Sebastian, Spain (GRID:grid.452382.a) (ISNI:0000 0004 1768 3100); Ikerbasque, Basque Foundation for Science, Bilbao, Spain (GRID:grid.424810.b) (ISNI:0000 0004 0467 2314) 
19  Donostia International Physics Center (DIPC), Donostia-San Sebastian, Spain (GRID:grid.452382.a) (ISNI:0000 0004 1768 3100) 
20  Lawrence Berkeley National Laboratory (LBNL), Berkeley, U.S.A. (GRID:grid.184769.5) (ISNI:0000 0001 2231 4551) 
21  Universidad Antonio Nariño, Centro de Investigación en Ciencias Básicas y Aplicadas, Bogotá, Colombia (GRID:grid.440783.c) (ISNI:0000 0001 2219 7324) 
22  Iowa State University, Department of Physics and Astronomy, Ames, U.S.A. (GRID:grid.34421.30) (ISNI:0000 0004 1936 7312) 
23  Ben-Gurion University of the Negev, Nuclear Engineering Unit, Faculty of Engineering Sciences, Beer-Sheva, Israel (GRID:grid.7489.2) (ISNI:0000 0004 1937 0511); Nuclear Research Center Negev, Beer-Sheva, Israel (GRID:grid.419373.b) (ISNI:0000 0001 2230 3545) 
24  Universidad de Santiago de Compostela, Instituto Gallego de Física de Altas Energías, Santiago de Compostela, Spain (GRID:grid.11794.3a) (ISNI:0000000109410645); Instituto de Física Corpuscular (IFIC), CSIC & Universitat de València, Paterna, Spain (GRID:grid.470047.0) (ISNI:0000 0001 2178 9889) 
25  Universidad Autónoma de Madrid, Departamento de Física Teórica, Madrid, Spain (GRID:grid.5515.4) (ISNI:0000000119578126) 
26  Universitat Politècnica de València, Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC, Valencia, Spain (GRID:grid.157927.f) (ISNI:0000 0004 1770 5832); Instituto de Física Corpuscular (IFIC), CSIC & Universitat de València, Paterna, Spain (GRID:grid.470047.0) (ISNI:0000 0001 2178 9889) 
27  Laboratorio Subterráneo de Canfranc, Canfranc Estación, Spain (GRID:grid.499304.3) 
28  Universitat de Girona, Escola Politècnica Superior, Girona, Spain (GRID:grid.5319.e) (ISNI:0000 0001 2179 7512) 
29  Donostia International Physics Center (DIPC), Donostia-San Sebastian, Spain (GRID:grid.452382.a) (ISNI:0000 0004 1768 3100); Laboratorio Subterráneo de Canfranc, Canfranc Estación, Spain (GRID:grid.499304.3) 
30  Texas A&M University, Department of Physics and Astronomy, College Station, U.S.A. (GRID:grid.264756.4) (ISNI:0000 0004 4687 2082); University of Texas at Austin, Austin, U.S.A. (GRID:grid.89336.37) (ISNI:0000 0004 1936 9924) 
31  Texas A&M University, Department of Physics and Astronomy, College Station, U.S.A. (GRID:grid.264756.4) (ISNI:0000 0004 4687 2082) 
Publication year
2021
Publication date
Feb 2021
Publisher
Springer Nature B.V.
e-ISSN
10298479
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1007/JHEP02(2021)203
ProQuest document ID
2494556100
Copyright
© The Author(s) 2021. This work is published under CC-BY 4.0 (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.