Double-Weak Decays of ${}^{124}$Xe and ${}^{136}$Xe in the XENON1T and XENONnT Experiments

Abstract

We present results on the search for double-electron capture ($2\nu \text{ECEC}$) of ${}^{124}$Xe and neutrinoless double-$\beta$ decay ($0\nu \beta \beta$) of ${}^{136}$Xe in XENON1T. We consider captures from the K- up to the N-shell in the $2\nu \text{ECEC}$ signal model and measure a total half-life of $T_{1/2}^{2\nu \text{ECEC}}=(1.1\pm 0.2_{\text{stat}}\pm 0.1_{\text{sys}})\times 10^{22}\text{yr}$ with a $0.87\text{kg}\times \text{yr}$ isotope exposure. The statistical significance of the signal is $7.0\sigma$. We use XENON1T data with $36.16\text{kg}\times \text{yr}$ of ${}^{136}$Xe exposure to search for $0\nu \beta \beta$. We find no evidence of a signal and set a lower limit on the half-life of $T_{1/2}^{0\nu \beta \beta }>1.2\times 10^{24}\text{yr}\text{at}90\%\text{CL}$. This is the best result from a dark matter detector without an enriched target to date. We also report projections on the sensitivity of XENONnT to $0\nu \beta \beta$. Assuming a $275\text{kg}\times \text{yr}$ ${}^{136}$Xe exposure, the expected sensitivity is $T_{1/2}^{0\nu \beta \beta }>2.1\times 10^{25}\text{yr}\text{at}90\%\text{CL}$, corresponding to an effective Majorana mass range of $⟨m_{\beta \beta }⟩<(0.19-0.59){\text{eV/c}}^2$.

23 pages, 14 figures, 9 tables, version accepted for publication in Phys. Rev. C

References in corpus (20)

• The fate of hints: updated global analysis of three-flavor neutrino oscillations
• Status and Future of Nuclear Matrix Elements for Neutrinoless Double-Beta Decay: A Review
• Phase space factors for double-$\beta$ decay
• Excess Electronic Recoil Events in XENON1T
• Final Results of GERDA on the Search for Neutrinoless Double-$\beta$ Decay
• Projected WIMP Sensitivity of the XENONnT Dark Matter Experiment
• First observation of two-neutrino double electron capture in ${}^{124}$Xe with XENON1T
• New Limit for Neutrinoless Double-Beta Decay of ${}^{100}$Mo from the CUPID-Mo Experiment
• XENON1T Dark Matter Data Analysis: Signal & Background Models, and Statistical Inference
• Precision Analysis of the ${}^{136}$Xe Two-Neutrino $\beta \beta$ Spectrum in KamLAND-Zen and Its Impact on the Quenching of Nuclear Matrix Elements
• Qualification Tests of the R11410-21 Photomultiplier Tubes for the XENON1T Detector
• Searching for New Physics in Two-Neutrino Double Beta Decay
• Two-Neutrino Double Beta Decay with Sterile Neutrinos
• Background Measurements in the Gran Sasso Underground Laboratory
• ${}^{222}$Rn emanation measurements for the XENON1T experiment
• Kiloton-scale xenon detectors for neutrinoless double beta decay and other new physics searches
• Search for Two-Neutrino Double Electron Capture of ${}^{124}$Xe with XENON100
• Search for Light Exotic Fermions in Double-Beta Decays
• Detection prospects for the second-order weak decays of ${}^{124}$Xe in multi-tonne xenon time projection chambers
• Application and modeling of an online distillation method to reduce krypton and argon in XENON1T

Cited by in corpus (23)

• Search for New Physics in Electronic Recoil Data from XENONnT
• Dark Matter Search Results from 4.2 Tonne-Years of Exposure of the LUX-ZEPLIN (LZ) Experiment
• Dark Matter Search Results from 1.54 Tonne$\cdot$Year Exposure of PandaX-4T
• PandaX-xT: a Multi-ten-tonne Liquid Xenon Observatory at the China Jinping Underground Laboratory
• WIMP Dark Matter Search using a 3.1 Tonne-Year Exposure of the XENONnT Experiment
• Background Determination for the LUX-ZEPLIN (LZ) Dark Matter Experiment
• A Review of NEST Models for Liquid Xenon and Exhaustive Comparison to Other Approaches
• Exploring New Physics with PandaX-4T Low Energy Electronic Recoil Data
• Predicting the neutrinoless double-beta decay matrix element of ${}^{136}$Xe using a statistical approach
• Neutrinoless Double Beta Decay Sensitivity of the XLZD Rare Event Observatory
• Self-consistent calculations for atomic electron capture
• Two-neutrino double electron capture of ${}^{124}$Xe in the first LUX-ZEPLIN exposure
• Search for Cosmic-ray Boosted Sub-MeV Dark-Matter-Electron Scattering in PandaX-4T
• Theoretical analysis and predictions for the double electron capture of ${}^{124}$Xe
• Comprehensive Review of 2$\beta$ Decay Half-Lives
• Searching for Neutrinoless Double-Beta Decay of ${}^{136}$Xe with PandaX-4T
• Combining Hybrid and Opaque Scintillator Techniques in the Search for Double Beta Plus Decays
• Measurements and models of enhanced recombination following inner-shell vacancies in liquid xenon
• Effective field theories for collective excitations of atomic nuclei
• Large-scale shell-model study of 2$\nu$ECEC process in ${}^{78}$Kr
• Preparation and measurement of an ${}^{37}$Ar source for liquid xenon detector calibration
• A Semi-Empirical Formula for Two-Neutrino Double-Beta Decay
• Large-scale shell-model investigation of $2\nu$ECEC in ${}^{132}$Ba and ${}^{78}$Kr