Электронный каталог

Статья

Acharya, S.
First Results on the Search for Lepton Number Violating Neutrinoless Double-*b Decay with the LEGEND-200 Experiment / S.Acharya, M.Fomina, Y.Gurov, K.Gusev, A.Klimenko, O.Kochetov, A.Lubashevskiy, I.Nemchenok, S.Rozov, N.Rumyantseva, V.Sandukovsky, K.Shakhov, E.Shevchik, M.Shirchenko, A.Smolnikov, V.Tretyak, S.Vasilyev, E.Yakushev, D.Zinatulina, [a.o.]. – Text : electronic // Physical Review Letters. – 2026. – Vol. 136, No. 2. – P. 022701. – URL: https://doi.org/10.1103/25tk-nctn. – Bibliogr.: 78.

The LEGEND Collaboration is searching for neutrinoless double-beta (0νββ) decay by operating highpurity germanium detectors enriched in *7*6Ge in a low-background liquid argon environment. Building on key technological innovations from the GERmanium Detector Array (GERDA) experiment and the MAJORANA DEMONSTRATOR experiment, LEGEND-200 has performed a first 0νββ decay search based on 61.0 kg yr of data. Over half of this exposure comes from our highest performing detectors, including newly developed inverted-coaxial detectors, and is characterized by an estimated background level of 0.5&sup(+0.3)&sub(−0.2) cts=(keV ton yr) in the 0νββ decay signal region. A combined analysis of data from GERDA, the MAJORANA DEMONSTRATOR, and LEGEND-200, characterized by a 90% confidence level exclusion sensitivity of 2.8 × 10*2*6 yr on the half-life of 0νββ decay, reveals no evidence for a signal and sets a new observed lower limit at T&sup(0ν)&sub(1/2) > 1.9 × 10*2*6 yr (90% confidence level). Assuming the decay is mediated by Majorana neutrinos, this corresponds to an upper limit on the effective Majorana mass in the range m&sub(ββ) < 75–200 meV, depending on the adopted nuclear matrix element.



ОИЯИ = ОИЯИ (JINR)2026
Спец.(статьи,препринты) = С 341.1б - Бета-распад и К-захват. Схемы распада и спектры