Authors
Eduardo Cortina Gil, Alina Kleimenova, E Minucci, S Padolski, P Petrov, A Shaikhiev, R Volpe, Toshio Numao, B Velghe, D Bryman, J Fu, T Husek, J Jerhot, K Kampf, M Zamkovsky, R Aliberti, G Khoriauli, Jonas Kunze, D Lomidze, R Marchevski, L Peruzzo, M Vormstein, R Wanke, P Dalpiaz, M Fiorini, I Neri, A Norton, F Petrucci, H Wahl, A Cotta Ramusino, A Gianoli, E Iacopini, G Latino, M Lenti, A Parenti, A Bizzeti, F Bucci, A Antonelli, G Georgiev, V Kozhuharov, G Lanfranchi, S Martellotti, M Moulson, T Spadaro, F Ambrosino, T Capussela, M Corvino, D Di Filippo, P Massarotti, M Mirra, M Napolitano, G Saracino, G Anzivino, F Brizioli, E Imbergamo, R Lollini, R Piandani, C Santoni, M Barbanera, P Cenci, B Checcucci, P Lubrano, M Lupi, M Pepe, M Piccini, F Costantini, L Di Lella, N Doble, M Giorgi, S Giudici, G Lamanna, E Lari, E Pedreschi, M Sozzi, C Cerri, R Fantechi, L Pontisso, F Spinella, I Mannelli, G D’Agostini, M Raggi, A Biagioni, E Leonardi, A Lonardo, P Valente, P Vicini, R Ammendola, V Bonaiuto, A Fucci, A Salamon, F Sargeni, R Arcidiacono, B Bloch-Devaux, M Boretto, E Menichetti, E Migliore, D Soldi, C Biino, A Filippi, F Marchetto, J Engelfried, N Estrada-Tristan, AM Bragadireanu, SA Ghinescu, OE Hutanu, A Baeva, D Baigarashev, D Emelyanov, T Enik, V Falaleev, V Kekelidze, A Korotkova, L Litov, D Madigozhin, M Misheva, N Molokanova, S Movchan, I Polenkevich, Y Potrebenikov, S Shkarovskiy, A Zinchenko, S Fedotov, E Gushchin, A Khotyantsev, Y Kudenko, V Kurochka, M Medvedeva, A Mefodev, S Kholodenko, V Kurshetsov, V Obraztsov, A Ostankov, V Semenov, V Sugonyaev, O Yushchenko, L Bician, T Blazek, V Cerny, Z Kucerova, J Bernhard, A Ceccucci, H Danielsson, N De Simone, F Duval, B Döbrich, L Federici, E Gamberini, L Gatignon, R Guida, F Hahn
Publication date
2021/2
Journal
Journal of High Energy Physics
Volume
2021
Issue
2
Pages
1-27
Publisher
Springer Berlin Heidelberg
Description
The NA62 experiment at the CERN SPS reports a study of a sample of 4× 10 9 tagged π 0 mesons from K+→ π+ π 0 (γ), searching for the decay of the π 0 to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4. 4× 10− 9 is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model-independent upper limit on the branching ratio for the decay K+→ π+ X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c 2 and rest lifetime greater than 100 ps. Model-dependent upper limits are obtained assuming X to be an axion-like particle with dominant fermion couplings or a dark scalar mixing with the Standard Model Higgs boson.
Scholar articles
E Cortina Gil, A Kleimenova, E Minucci, S Padolski… - Journal of High Energy Physics, 2021