Final published version
Licence: CC BY: Creative Commons Attribution 4.0 International License
Research output: Contribution to Journal/Magazine › Journal article › peer-review
| <mark>Journal publication date</mark> | 10/04/2019 |
|---|---|
| <mark>Journal</mark> | Physics Letters B |
| Volume | 791 |
| Number of pages | 11 |
| Pages (from-to) | 156-166 |
| Publication Status | Published |
| Early online date | 23/02/19 |
| <mark>Original language</mark> | English |
The NA62 experiment at the CERN SPS reports the first search for K + →π + νν¯ using the decay-in-flight technique, based on a sample of 1.21×10 11 K + decays collected in 2016. The single event sensitivity is 3.15×10 −10 , corresponding to 0.267 Standard Model events. One signal candidate is observed while the expected background is 0.152 events. This leads to an upper limit of 14×10 −10 on the K + →π + νν¯ branching ratio at 95% CL.