Observation of the K + → π + ν ν ¯ $$ {K}^{+}\to {\pi}^{+}\nu \overline{\nu} $$ decay and measurement of its branching ratio

Bibliographic Details
Title: Observation of the K + → π + ν ν ¯ $$ {K}^{+}\to {\pi}^{+}\nu \overline{\nu} $$ decay and measurement of its branching ratio
Authors: 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, L. Peruzzo, C. Polivka, S. Schuchmann, H. Wahl, R. Wanke, P. Dalpiaz, R. Negrello, I. Neri, F. Petrucci, M. Soldani, L. Bandiera, N. Canale, A. Cotta Ramusino, A. Gianoli, M. Romagnoni, A. Sytov, M. Lenti, P. Lo Chiatto, I. Panichi, G. Ruggiero, A. Bizzeti, F. Bucci, A. Antonelli, V. Kozhuharov, G. Lanfranchi, S. Martellotti, M. Moulson, T. Spadaro, G. Tinti, F. Ambrosino, M. D’Errico, R. Fiorenza, M. Francesconi, R. Giordano, P. Massarotti, M. Mirra, M. Napolitano, I. Rosa, G. Saracino, G. Anzivino, P. Cenci, V. Duk, R. Lollini, P. Lubrano, M. Pepe, M. Piccini, F. Costantini, M. Giorgi, S. Giudici, G. Lamanna, E. Lari, E. Pedreschi, J. Pinzino, M. Sozzi, R. Fantechi, F. Spinella, I. Mannelli, M. Raggi, A. Biagioni, P. Cretaro, O. Frezza, A. Lonardo, M. Turisini, P. Vicini, R. Ammendola, V. Bonaiuto, A. Fucci, A. Salamon, F. Sargeni, R. Arcidiacono, B. Bloch-Devaux, E. Menichetti, E. Migliore, C. Biino, A. Filippi, F. Marchetto, D. Soldi, Y. Mukhamejanov, A. Mukhamejanova, N. Saduyev, S. Sakhiyev, A. Briano Olvera, J. Engelfried, N. Estrada-Tristan, R. Piandani, M. A. Reyes Santos, K. A. Rodriguez Rivera, P. Boboc, A. M. Bragadireanu, S. A. Ghinescu, O. E. Hutanu, T. Blazek, V. Cerny, T. Velas, R. Volpe, J. Bernhard, L. Bician, M. Boretto, F. Brizioli, A. Ceccucci, M. Corvino, H. Danielsson, F. Duval, L. Federici, E. Gamberini, R. Guida, E. B. Holzer, B. Jenninger, Z. Kucerova, G. Lehmann Miotto, P. Lichard, K. Massri, E. Minucci, M. Noy, V. Ryjov, J. Swallow, M. Zamkovsky, X. Chang, A. Kleimenova, R. Marchevski, J. R. Fry, F. Gonnella, E. Goudzovski, J. Henshaw, C. Kenworthy, C. Lazzeroni, C. Parkinson, A. Romano, C. Sam, J. Sanders, A. Sergi, A. Shaikhiev, A. Tomczak, H. Heath, D. Britton, A. Norton, D. Protopopescu, J. B. Dainton, L. Gatignon, R. W. L. Jones, P. Cooper, D. Coward, P. Rubin, A. Baeva, D. Baigarashev, V. Bautin, D. Emelyanov, T. Enik, V. Falaleev, V. Kekelidze, D. Kereibay, A. Korotkova, L. Litov, D. Madigozhin, M. Misheva, N. Molokanova, I. Polenkevich, Yu. Potrebenikov, K. Salamatin, S. Shkarovskiy, S. Fedotov, K. Gorshanov, E. Gushchin, S. Kholodenko, A. Khotyantsev, Y. Kudenko, V. Kurochka, V. Kurshetsov, A. Mefodev, V. Obraztsov, A. Okhotnikov, A. Sadovskiy, V. Sugonyaev, O. Yushchenko
Source: Journal of High Energy Physics, Vol 2025, Iss 2, Pp 1-26 (2025)
Publisher Information: SpringerOpen, 2025.
Publication Year: 2025
Collection: LCC:Nuclear and particle physics. Atomic energy. Radioactivity
Subject Terms: Branching fraction, Rare Decay, Flavour Physics, Other Experiments, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
More Details: Abstract A measurement of the K + → π + ν ν ¯ $$ {K}^{+}\to {\pi}^{+}\nu \overline{\nu} $$ 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 + ν ν ¯ = 13.0 − 3.0 + 3.3 × 10 − 11 $$ \mathcal{B}\left({K}^{+}\to {\pi}^{+}\nu \overline{\nu}\right)=\left({13.0}_{-3.0}^{+3.3}\right)\times {10}^{-11} $$ is reported. With 51 signal candidates observed and an expected background of 18 − 2 + 3 $$ {18}_{-2}^{+3} $$ events, B K + → π + ν ν ¯ $$ \mathcal{B}\left({K}^{+}\to {\pi}^{+}\nu \overline{\nu}\right) $$ becomes the smallest branching ratio measured with a signal significance above 5σ.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1029-8479
Relation: https://doaj.org/toc/1029-8479
DOI: 10.1007/JHEP02(2025)191
Access URL: https://doaj.org/article/c474c15776674dcc9f59dde0683f08f5
Accession Number: edsdoj.474c15776674dcc9f59dde0683f08f5
Database: Directory of Open Access Journals
More Details
ISSN:10298479
DOI:10.1007/JHEP02(2025)191
Published in:Journal of High Energy Physics
Language:English