2025-03-19 スイス連邦工科大学ローザンヌ校（EPFL）
＜関連情報＞
- https://actu.epfl.ch/news/in-a-first-for-switzerland-epfl-contributes-to-kao/
- https://link.springer.com/article/10.1007/JHEP02(2025)191
- https://www.sciencedirect.com/science/article/pii/S0370269325001054
K+→π+νν¯崩壊の観測と分岐比の測定 Observation of the K+→π+νν¯ decay and measurement of its branching ratio
The NA62 collaboration,E. Cortina Gil,J. Jerhot,N. Lurkin,T. Numao,B. Velghe,V. W. S. Wong,D. Bryman,Z. Hives,T. Husek,K. Kampf,M. Kolesar,M. Koval,B. De Martino,M. Perrin-Terrin,L. Petit,B. Döbrich,S. Lezki,J. Schubert,A. T. Akmete,R. Aliberti,M. Ceoletta,L. Di Lella,N. Doble,… O. Yushchenko
Journal of High Energy Physics Published:27 February 2025
DOI:https://doi.org/10.1007/JHEP02(2025)191
Abstract
A measurement of the K+→π+νν¯ decay by the NA62 experiment at the CERN SPS is presented, using data collected in 2021 and 2022. This dataset was recorded, after modifications to the beamline and detectors, at a higher instantaneous beam intensity with respect to the 2016–2018 data taking. Combining NA62 data collected in 2016–2022, a measurement of B(K+→π+νν¯)=(13.0+3.3−3.0)×10−11 is reported. With 51 signal candidates observed and an expected background of 18+3−2 events, B(K+→π+νν¯) becomes the smallest branching ratio measured with a signal significance above 5σ.
NA62実験におけるタグ付きニュートリノの初検出 First detection of a tagged neutrino in the NA62 experiment
The NA62 Collaboration
Physics Letters B Available online: 27 February 2025
DOI:https://doi.org/10.1016/j.physletb.2025.139345
Abstract
The NA62 experiment at the CERN SPS reports the first detection of a tagged neutrino candidate based on the data collected in 2022. The candidate consists of a K+→μ+νμ decay where the charged particles are reconstructed and the neutrino is detected through a charged-current interaction in a liquid krypton calorimeter.
