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arXiv · 2304.12271

A study of the $K^+ \to \pi^0 e^+ \nu \gamma$ decay

The NA62 Collaboration
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Abstract

A sample of $1.3 \times 10^5$ $K^+ \to \pi^0 e^+ \nu \gamma$ candidates with less than 1% background was collected by the NA62 experiment at the CERN SPS in 2017-2018. Branching fraction measurements are obtained at percent relative precision in three restricted kinematic regions, improving on existing results by a factor larger than two. An asymmetry, possibly related to T-violation, is investigated with no evidence observed within the achieved precision.

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The NA62 Collaboration. 2023-04-24. A study of the $K^+ \to \pi^0 e^+ \nu \gamma$ decay. https://doi.org/10.1007/jhep09(2023)040

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