Abstract
The K+→π+νν decay is highly suppressed in the Standard Model, making the
branching fraction extremely sensitive to contributions from new particles.
Moreover, that same branching fraction can be precisely calculated in
theoretical models. The combination of these facts makes the K+→
π+νν decay
a powerful probe of the Standard Model flavour sector.
The NA62 experiment at the CERN SPS began taking data in autumn last year.
The goal of NA62 is to collect about 100 K+→π+νν events within two years of
data taking, which means isolating the right 100 events from around
1013
K+
decays. Background rejection on such a scale requires a cutting-edge
experiment such as NA62. The 100 K+→π+νν events will provide the basis for
the world’s most precise measurement of the K+→π+νν branching fraction,
which will impose severe constraints on physics beyond the Standard Model.
In light of the pilot physics run that took place in autumn last year the
status of NA62 will be presented. The beam line and detector systems will be
outlined, including a description of the trigger. The similarities and
differences of contemporary experiments, such as those at the LHC, will be
identified. The expected physics performance, and prospects for discovery of
new physics phenomena, will be examined.