2019/10/16 by Melissa A. Hutcheson, Hutcheson, Melissa A.
Physics and Astronomy · #Black Holes and Theoretical Physics #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Instrumentation and Detectors (physics.ins-det) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.1910.07585
openalex publication_date 2019/10/16 · openalex created_date 2022/07/28 · openalex updated_date 2026/07/28
The KOTO experiment at the J-PARC research facility in Tokai, Japan aims to observe and measure the rare decay of the neutral kaon, KL0 → π0 νν. This decay has a Standard Model (SM) predicted branching ratio (BR) of (3.00 ± 0.30) × 10-11. While this decay is extremely rare, it is one of the best decays in the quark sector to probe for new physics beyond the SM due to small theoretical uncertainties. The E391a experiment at KEK 12-GeV PS previously searched for KL0 → π0 νν events and set a limit of BR(KL0 → π0 νν) < 2.6 × 10-8 in 2010. In 2018, KOTO set a new experimental limit of BR(KL0 → π0 νν) < 3.0 × 10-9 from data collected in 2015, improving the best experimental upper limit by an order of magnitude. From 2016 to 2018, KOTO collected around 1.5 times more data than in 2015, and the analysis of this dataset is underway. This report covers the progress and current status of the 2016-2018 data analysis.