# The Beam and detector of the NA62 experiment at CERN

## TL;DR

The NA62 experiment at CERN uses advanced detector technology to measure rare kaon decays, aiming to test the Standard Model and explore new physics through precise experimental and theoretical comparisons.

## Contribution

This paper details the design, construction, and initial performance of the NA62 detector system, highlighting innovations in low-mass tracking for rare decay measurements.

## Key findings

- Successful detector commissioning in 2014-2015
- High-precision tracking achieved with low-mass devices
- Potential to measure rare decay branching fractions accurately

## Abstract

NA62 is a fixed-target experiment at the CERN SPS dedicated to measurements of rare kaon decays. Such measurements, like the branching fraction of the $K^{+} \rightarrow \pi^{+} \nu \bar\nu$ decay, have the potential to bring significant insights into new physics processes when comparison is made with precise theoretical predictions. For this purpose, innovative techniques have been developed, in particular, in the domain of low-mass tracking devices. Detector construction spanned several years from 2009 to 2014. The collaboration started detector commissioning in 2014 and will collect data until the end of 2018. The beam line and detector components are described together with their early performance obtained from 2014 and 2015 data.