Abstract
The MAJORANA DEMONSTRATOR was an ultra-low-background experiment designed for neutrinoless doublebeta decay (0νββ) investigation in 76Ge. Located at the Sanford Underground Research Facility in Lead, South Dakota, the DEMONSTRATOR utilized modular high-purity Ge detector arrays within shielded vacuum cryostats, operating deep underground. The arrays, with a capacity of up to 40.4 kg (27.2 kg enriched to ∼88% in 76Ge), have accumulated the full data set, totaling 64.5 kg yr of enriched active exposure and 27.4 kg yr of exposure for natural detectors. Our updated search improves previously explored three-nucleon decay modes in Ge isotopes, setting new partial lifetime limits of 1.83 × 1026 yr (90% confidence level) for 76Ge(ppp)→73Cu e+ π+ π+ and 76Ge(ppn)→73Zn e+ π+. The partial lifetime limit for the fully inclusive triproton decay mode of 76Ge is found to be 2.1 × 1025 yr. Furthermore, we have updated limits for corresponding multinucleon decays.
| Original language | English |
|---|---|
| Pages (from-to) | L0225011-L0225017 |
| Journal | Physical Review C |
| Volume | 112 |
| Issue number | 2 |
| DOIs | |
| State | Published - Aug 7 2025 |
Funding
Research & Development (LDRD) program at Lawrence Berkeley National Laboratory for this work. We gratefully acknowledge the support of the U.S. Department of Energy through the Los Alamos National Laboratory LDRD Program, the Oak Ridge National Laboratory LDRD Program, and the Pacific Northwest National Laboratory LDRD Program for this work. This research used resources provided by the Oak This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contracts and Awards No. DE-AC02-05CH11231, No. DE-AC05-00OR22725, No. DE-AC05-76RL0130, No. DE-FG02-97ER41020, No. DE-FG02-97ER41033, No. DE-FG02-97ER41041, No. DE-SC0012612, No. DE-SC0014445, No. DE-SC0017594, No. DE-SC0018060, No. DE-SC0022339, and LANLEM77/ LANLEM78. We acknowledge support from the Particle Astrophysics Program and Nuclear Physics Program of the National Science Foundation through Grants No. MRI-0923142, No. PHY-1003399, No. PHY-1102292, No. PHY-1206314, No. PHY-1614611, No. PHY-13407204, No. PHY-1812409, and PHY-2209530. Ridge Leadership Computing Facility at Oak Ridge National Laboratory and by the National Energy Research Scientific Computing Center, a U.S. Department of Energy Office of Science User Facility. We thank our hosts and colleagues at the Sanford Underground Research Facility for their support. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contracts and Awards No. DE-AC02-05CH11231, No. DE-AC05-00OR22725, No. DE-AC05-76RL0130, No. DE-FG02-97ER41020, No. DE-FG02-97ER41033, No. DE-FG02-97ER41041, No. DE-SC0012612, No. DE-SC0014445, No. DE-SC0017594, No. DE-SC0018060, No. DE-SC0022339, and LAN-LEM77/LANLEM78. We acknowledge support from the Particle Astrophysics Program and Nuclear Physics Program of the National Science Foundation through Grants No. MRI-0923142, No. PHY-1003399, No. PHY-1102292, No. PHY-1206314, No. PHY-1614611, No. PHY-13407204, No. PHY-1812409, and PHY-2209530. We gratefully acknowledge the support of the Laboratory Directed