We have measured the ratio R = Gamma(K-L --> gammagamma)/Gamma(K-L --> pi(0)pi(0)pi(0)) using the KLOE detector. From a sample of similar to10(9) phi-mesons produced at DAPhiNE, the Frascati phi-factory, we select similar to1.6 x 10(8) K-L-mesons tagged by observing K-S --> pi(+)pi(-) following the reaction e(+)e(-) --> phi --> KLKS. From this sample we select 27,375 K-L --> gammagamma events and obtain R = (2.79 +/- 0.02(stat) +/- 0.02(syst)) X 10(-3). Using the world average value for BR(K-L --> pi(0)pi(0)pi(0)), we obtain BR(K-L --> gammagamma) = (5.89 +/- 0.07 +/- 0.08) x 10(-4) where the second error is due to the uncertainty on the pi(0)pi(0)pi(0) branching fraction. (C) 2003 Published by Elsevier B.V.
Adinolfi, M., Aloisio, A., Ambrosino, F., Antonelli, A., Antonelli, M., Bacci, C., et al. (2003). Measurement of the ratio Gamma(K-L ->gamma gamma)/Gamma(K-L ->pi(0)pi(0)pi(0)) with the KLOE detector. PHYSICS LETTERS. SECTION B, 566, 61-69 [http://dx.doi.org/10.1016/S0370-2693(03)00810-4].
Measurement of the ratio Gamma(K-L ->gamma gamma)/Gamma(K-L ->pi(0)pi(0)pi(0)) with the KLOE detector
CARBONI, GIOVANNI;MESSI, ROBERTO;SANTOVETTI, EMANUELE;
2003-01-01
Abstract
We have measured the ratio R = Gamma(K-L --> gammagamma)/Gamma(K-L --> pi(0)pi(0)pi(0)) using the KLOE detector. From a sample of similar to10(9) phi-mesons produced at DAPhiNE, the Frascati phi-factory, we select similar to1.6 x 10(8) K-L-mesons tagged by observing K-S --> pi(+)pi(-) following the reaction e(+)e(-) --> phi --> KLKS. From this sample we select 27,375 K-L --> gammagamma events and obtain R = (2.79 +/- 0.02(stat) +/- 0.02(syst)) X 10(-3). Using the world average value for BR(K-L --> pi(0)pi(0)pi(0)), we obtain BR(K-L --> gammagamma) = (5.89 +/- 0.07 +/- 0.08) x 10(-4) where the second error is due to the uncertainty on the pi(0)pi(0)pi(0) branching fraction. (C) 2003 Published by Elsevier B.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.