Precision Analysis of the Xe-136 Two-Neutrino beta beta Spectrum in KamLAND-Zen and Its Impact on the Quenching of Nuclear Matrix Elements
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21670%2F19%3A00338229" target="_blank" >RIV/68407700:21670/19:00338229 - isvavai.cz</a>
Result on the web
<a href="https://doi.org/10.1103/PhysRevLett.122.192501" target="_blank" >https://doi.org/10.1103/PhysRevLett.122.192501</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1103/PhysRevLett.122.192501" target="_blank" >10.1103/PhysRevLett.122.192501</a>
Alternative languages
Result language
angličtina
Original language name
Precision Analysis of the Xe-136 Two-Neutrino beta beta Spectrum in KamLAND-Zen and Its Impact on the Quenching of Nuclear Matrix Elements
Original language description
We present a precision analysis of the Xe-136 two-neutrino beta beta electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino beta beta rate allows us to measure the ratio of the leading and subleading 2 nu beta beta nuclear matrix elements (NMEs), xi(2 nu)(31) = -0.26(-0.25)(+0.31). Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the xi(2 nu)(31) range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted xi(2 nu)(31) values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless beta beta decay, xi(2 nu)(31) provides new insights toward reliable neutrinoless beta beta NMEs.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10304 - Nuclear physics
Result continuities
Project
<a href="/en/project/EF16_019%2F0000766" target="_blank" >EF16_019/0000766: Engineering applications of microworld physics</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2019
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Physical Review Letters
ISSN
0031-9007
e-ISSN
1079-7114
Volume of the periodical
122
Issue of the periodical within the volume
19
Country of publishing house
US - UNITED STATES
Number of pages
7
Pages from-to
"192501-1"-"192501-7"
UT code for WoS article
000468227800004
EID of the result in the Scopus database
2-s2.0-85065833472