Precise measurement of (K1e (g))/(K1k (g)) and study of K1e g

• Published in: The European physical journal. C, Particles and fields Vol. 64; no. 4; pp. 627 - 636
• Main Authors: Ambrosino, F, Antonelli, A, Antonelli, M, Archilli, F, Beltrame, P, Bencivenni, G, Bini, C, Bloise, C, Bocchetta, S, Bossi, F, Branchini, P, Capon, G, Capriotti, D, Capussela, T, Ceradini, F, Ciambrone, P, Lucia, EDe, Santis, ADe, Simone, PDe, Zorzi, GDe, Denig, A, Domenico, ADi, Donato, CDi, Micco, BDi, Dreucci, M, Felici, G, Fiore, S, Franzini, P, Gatti, C, Gauzzi, P, Giovannella, S, Graziani, E, Jacewicz, M, Kulikov, V, Lanfranchi, G, Lee-Franzini, J, Martini, M, Massarotti, P, Meola, S, Miscetti, S, Moulson, M, Mueller, S, Murtas, F, Napolitano, M, Nguyen, F, Palutan, M, Passeri, A, Patera, V, Santangelo, P, Sciascia, B, Sibidanov, A, Spadaro, T, Tortora, L, Valente, P, Venanzoni, G, Versaci, R
• Format: Journal Article
• Language: English
• Published: 01.12.2009
• Subjects: Decay rate; Detectors; Leptons; Luminosity; Mathematical models; Photons
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-009-1177-x

We present a precise measurement of the ratio R sub(K)=(K1e (g))/(K1k (g)) and a study of the radiative process K1e g, performed with the KLOE detector. The results are based on data collected at the Frascati e super(+) e super(-) collider DANE for an integrated luminosity of 2.2 fb super(-1). We find R sub(K) =(2.493c0.025 sub(stat)c 0.019 sub(syst))10 super(-5), in agreement with the Standard Model expectation. This result is used to improve constraints on parameters of the Minimal Supersymmetric Standard Model with lepton flavor violation. We also measured the differential decay rate d(K1e g)/dE sub(g) for photon energies 10<E sub(g)< 250 MeV. Results are compared with predictions from theory.