20–25 Aug 2023
Universität Hamburg
Europe/Berlin timezone

Recent results from precision measurements at the NA62 experiment

21 Aug 2023, 09:36
18m
Hörsaal C (Historic main building)

Hörsaal C

Historic main building

Edmund-Siemers-Allee 1
Parallel session talk Flavour Physics and CP Violation T08 Flavour Physics and CP Violation

Speaker

Andrea Bizzeti (University of Modena and Reggio Emilia, and INFN Sezione di Firenze, Italy)

Description

The NA62 experiment at CERN collected the world's largest dataset of charged kaon decays in 2016-2018, leading to the first measurement of the branching ratio of the ultra-rare $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay, based on 20 candidates. In this talk the NA62 experiment reports recent results from analyses of $K^+ \rightarrow \pi^0 e^+ \nu \gamma$, $K^+ \rightarrow \pi^+ \mu^+ \mu^-$ and $K^+\rightarrow \pi^+ \gamma \gamma$ decays, using a data sample recorded in 2017--2018. The radiative kaon decay $K^+ \rightarrow \pi^0 e^+ \nu \gamma$ (Ke3g) is studied with a data sample of O(100k) Ke3g candidates with sub-percent background contaminations. Results with the most precise measurements of the Ke3g branching ratios and T-asymmetry are presented. The $K^+ \rightarrow \pi^+ \mu^+ \mu^-$ sample comprises about 27k signal events with negligible background contamination, and the presented analysis results include the most precise determination of the branching ratio and the form factor. The $K^+ \rightarrow \pi^+ \gamma \gamma$ sample contains about 4k signal events with $10\%$ background contamination, and the analysis improves the precision of the branching ratio measurement by a factor of 3 with respect to the previous measurements.

Collaboration / Activity NA62

Primary authors

Andrea Bizzeti (University of Modena and Reggio Emilia, and INFN Sezione di Firenze, Italy) Andrea Bizzeti Angela Romano (University of Birmingham)

Presentation materials