2002/05/28 by M. Diwan, Milind V Diwan, Diwan, Milind V
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.48550/arxiv.hep-ex/0205089
23 pages 8 figures Talk given at Les Rencontres de Physique, La Thuile, Aosta Valley (Italy), March 3-9, 2002
arxiv created 2002/05/28 · openalex publication_date 2002/05/28 · arxiv updated 2009/11/30 · openalex created_date 2024/04/11 · openalex updated_date 2026/07/28
In this paper I will describe the search for rare kaon decay processes K+→ π+ νν and K0L → π0 νν. The small decay rate for these processes is considered a key prediction of the standard model. We searched for the charged kaon decay K+→ π+ νν using kaons decaying at rest in the E787 detector at Brookhaven National Laboratory in two different phase space regions: Region 1 with pion momentum above 205 MeV/c (the K+ → π+ π0 peak) and Region 2 with pion momentum below 205 MeV/c. We have found 2 events in Region 1 which is known to have small background (0.15+0.048-0.032). This observation leads to a branching ratio measurement of (1.57+1.75-0.82)× 10-10. We found 1 event in Region 2 with an expectation of 0.73± 0.18 background events. The observation from Region 2 is consistent with the branching ratio measured using Region 1. I will also describe new efforts underway to measure both the decay rates with much higher statistics.