First Results on the Rare Decay K+ → π+νν from the NA62 Experiment at CERN
Abstract
:1. Introduction
2. The NA62 Experiment
3. Principle of Measurement
- the main decay modes, and , which can enter the signal regions through non-Gaussian resolution and radiative tails of the squared missing mass;
- , through non-Gaussian resolution tails;
- and rarer processes such as , broadly distributed across the signal regions because of the neutrinos in the final state;
- events mimicking a decay, either originated along the beam line via inelastic interactions of the beam particles with the setup or produced by kaons that decay before entering the FV downstream to the last station of the GTK.
4. Event Selection
- definition of a positive kaon decay with a charged particle in the final state;
- positive pion identification;
- rejection of events with photons or any other activity in the final state;
- kinematic selection and definition of the signal regions.
5. Single Event Sensitivity
6. Background Estimation
7. Results
8. Conclusions
Funding
Conflicts of Interest
References
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Process | Expected Events in SR1 and SR2 |
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Upstream background | |
Total background |
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Gonnella, F. First Results on the Rare Decay K+ → π+νν from the NA62 Experiment at CERN. Universe 2018, 4, 130. https://doi.org/10.3390/universe4110130
Gonnella F. First Results on the Rare Decay K+ → π+νν from the NA62 Experiment at CERN. Universe. 2018; 4(11):130. https://doi.org/10.3390/universe4110130
Chicago/Turabian StyleGonnella, Francesco. 2018. "First Results on the Rare Decay K+ → π+νν from the NA62 Experiment at CERN" Universe 4, no. 11: 130. https://doi.org/10.3390/universe4110130
APA StyleGonnella, F. (2018). First Results on the Rare Decay K+ → π+νν from the NA62 Experiment at CERN. Universe, 4(11), 130. https://doi.org/10.3390/universe4110130