Determination of neutrino mass ordering in future 76Ge-based neutrinoless double-beta decay experiments
Abstract
Motivated by recent intensive experimental efforts on searching for neutrinoless double-beta decays, we perform a detailed analysis of the physics potential of the experiments based on 76Ge. Assuming no signals, current and future experiments could place a 90% lower limit on the half life T1/2 0 ν≳4 ×1026 yr and T1/2 0 ν≳7 ×1027 yr , respectively. Then, how to report an evidence for neutrinoless double-beta decays is addressed by following the Bayesian statistical approach. For the first time, we present a quantitative description of experimental power to distinguish between normal and inverted neutrino mass orderings. Taking an exposure of 104 kg yr and a background rate of 1 0-4 counts/(keV kg yr ) , we find that a moderate evidence for normal neutrino mass ordering (i.e., with a Bayes factor B given by ln (B )≃2.5 or a probability about 92.3% according to the Jeffreys scale) can be achieved if the true value of effective neutrino mass mβ β turns out to be below 0.01 eV.
- Publication:
-
Physical Review D
- Pub Date:
- January 2016
- DOI:
- 10.1103/PhysRevD.93.016008
- arXiv:
- arXiv:1508.05472
- Bibcode:
- 2016PhRvD..93a6008Z
- Keywords:
-
- High Energy Physics - Phenomenology;
- High Energy Physics - Experiment
- E-Print:
- 16 pages, 7 figures, the Jeffreys scale used, more discussions added, to appear in Phys. Rev. D