Testing the Standard Model at the NA62 experiment

The NA62 experiment at CERN is designed to study the fundamental particles that make up our universe. Its main goal is to observe a very rare particle decay: a positively charged kaon transforming into a positively charged pion, along with a neutrino and an antineutrino.

This specific type of decay is expected to happen very infrequently, and by precisely measuring how often it occurs, scientists aim to test our current understanding of particle physics, known as the Standard Model. They are also looking for any unexpected results that could point towards new physics beyond this established theory.

Observing this rare decay is a significant technical challenge, as it’s estimated to occur only about once in every ten billion kaon decays. To achieve this, NA62 uses a powerful beam of kaons and a complex system of detectors. These detectors are designed to accurately track particles and effectively filter out the much more common, unwanted background events.

Our NA62 team is involved in the data analysis of rare decays of kaons and neutral pions. We also contribute to the operation of the main tracker of the experiment, the STRAW spectrometer. We have recently published results with the most precise determination of the branching ratio (probability) of the K→πνν  decay, based on 51 observed signal event candidates in data collected in the years 2016–2022.

Contacts:

• Michal Kovaľ
• Tomáš Husek
• Ľuboš Bičian
• Karol Kampf
• Marián Kolesár
• Marjan Ćirković
• Elizabeth Long

Publications:

[1] NA62 Collaboration, Observation of the K+→π+νν decay and measurement of its branching ratio, JHEP 02 (2025) 191

[2] NA62 Collaboration, First search for K+→π0πμe decays, Phys.Lett.B 859 (2024) 139122

[3] NA62 Collaboration, Measurement of the K+ → π+γγ decay,  Phys.Lett.B 850 (2024) 138513

Registration at CERN

Instructions: Registration at CERN [cz]