First observation and measurement of the decay K±→π±e+e−γ

6533b82bfe1ef96bd128d672

RESEARCH PRODUCT

First observation and measurement of the decay K±→π±e+e−γ

Rainer Wanke R. Fantechi A. Ceccucci Andrea Bizzeti Marco Clemencic F. Costantini C. Cerri I. Polenkevich M. D. Wood Milene Calvetti G. Ruggiero G.m. Pierazzini J. Derre I. Mannelli A. Gonidec B. Vallage E. C. Swallow P. Rubin Roberta Arcidiacono H. D. Wahl M. Fidecaro Evgueni Goudzovski N. Doble H. Dibon G. Collazuol S. Balev M. Martini R. Winston B. Peyaud L. Masetti D. Coward Cristina Lazzeroni J.b. Cheze M. Scarpa T. Fonseca Martin M. Holder Mauro Raggi B. Renk Mauro Piccini P. Hristov Luca Fiorini A.j. Culling E. Marinova E. Monnier G. Neuhofer D.j. Munday G. Marel A. Winhart Nicola Cabibbo W. Kubischta M. Shieh C. Cheshkov V. Kozhuharov D.c. Cundy S. Stoynev Nicolo Cartiglia M. Pepe Cristina Biino Ivan Mikulec Lau Gatignon M. Savrie E. Iacopini A. A. Maier P. F. Dalpiaz P. Marouelli B. Bloch-devaux P. Cenci C. Handel M. Veltri F. Marchetto C. Damiani M.w. Slater L. Widhalm Manfred Jeitler W. Baldini G.e. Kalmus V. Falaleev A. Zinchenko M. Ziolkowski M. De Beer G. Anzivino J. R. Batley A. Peters S. Goy Lopez A. Norton M. Behler G. Bocquet Yu. Potrebenikov A. Nappi S. Wotton Vladimir Kekelidze S. Giudici M. Sozzi L. Dilella M. Wache Massimiliano Fiorini D. T. Madigozhin E. Mazzucato C. Morales Morales Mayda Velasco M. Markytan M. Lenti A. Gianoli Enrico Celeghini A. Dabrowski M. C. Petrucci Maulik R. Patel Konrad Kleinknecht M. Valdata-nappi F. Martelli M. Szleper Simone Bifani U. Moosbrugger E. Imbergamo A. Cotta Ramusino G. Lamanna Fabrizio Petrucci Leander Litov Alan W. Walker P. L. Frabetti A. Michetti N. A. Molokanova K. Eppard

subject

Physics Nuclear and High Energy Physics Antiparticle Chiral perturbation theory Meson 010308 nuclear & particles physics Branching fraction Hadron Analytical chemistry 01 natural sciences Nuclear physics Particle decay Pion 0103 physical sciences 010306 general physics Dimensionless quantity

description

Abstract Using the full data set of the NA48/2 experiment, the decay K ± → π ± e + e − γ is observed for the first time, selecting 120 candidates with 7.3 ± 1.7 estimated background events. With K ± → π ± π D 0 as normalisation channel, the branching ratio is determined in a model-independent way to be Br ( K ± → π ± e + e − γ , m e e γ > 260 MeV / c 2 ) = ( 1.19 ± 0.12 stat ± 0.04 syst ) × 10 −8 . This measured value and the spectrum of the e + e − γ invariant mass allow a comparison with predictions of chiral perturbation theory.

year	journal	country	edition	language
2008-01-01	Physics Letters B

https://doi.org/10.1016/j.physletb.2007.11.075