CERN Accelerating science

Article
Report number arXiv:2103.15389
Title Measurement of the very rare K++π+ν¯νπ+ν¯¯¯ν decay
Related titleMeasurement of the very rare K+π+νˉνK+π+ν¯ν decay
Author(s) NA62 Collaboration  Zeige alle 203 Autoren
Publication 2021-06-15
Imprint 2021-03-29
Number of pages 22
In: JHEP 2106 (2021) 093
DOI 10.1007/JHEP06(2021)093
Subject category hep-ex ; Particle Physics - Experiment
Accelerator/Facility, Experiment CERN SPS ; NA62
Abstract The NA62 experiment reports the branching ratio measurement BR(K+π+νˉν)=(10.6+4.03.4|stat±0.9syst)×1011(K+π+ν¯ν)=(10.6+4.03.4|stat±0.9syst)×1011 at 68% CL, based on the observation of 20 signal candidates with an expected background of 7.0 events from the total data sample collected at the CERN SPS during 2016-2018. This provides evidence for the very rare K+π+νˉνK+π+ν¯ν decay, observed with a significance of 3.4σσ. The experiment achieves a single event sensitivity of (0.839±0.054)×1011(0.839±0.054)×1011, corresponding to 10.0 events assuming the Standard Model branching ratio of (8.4±1.0)×1011(8.4±1.0)×1011. This measurement is also used to set limits on BR(K+π+XK+π+X), where XX is a scalar or pseudo-scalar particle. Details are given of the analysis of the 2018 data sample, which corresponds to about 80% of the total data sample.
Copyright/License preprint: (License: CC-BY-4.0)
publication: © 2021-2025 CERN (License: CC-BY-4.0), sponsored by SCOAP³



Corresponding record in: Inspire


 Datensatz erzeugt am 2021-03-31, letzte Änderung am 2024-08-08


Article from SCOAP3:
Volltext herunterladenPDF
Volltext:
Volltext herunterladenPDF
  • Send to ScienceWise.info