Measurements of the decay KL-->e+ e- gamma.
The E799-II (KTeV) experiment at Fermilab has collected 83 262 K(L)-->e+ e- gamma(gamma) events above a background of 79 events. We measure a decay width, normalized to the K(L)-->pi0pi0pi(D)0 (pi0-->gammagamma, pi0-->gammagamma, pi(D0-->e+ e- gamma(gamma)) decay width, of Gamma(K(L)-->e+e-gamma(gamma))/Gamma(K(L)-->pi0pi0pi(D)0)=(1.3302+/-0.0046(stat)+/-0.0102(syst)) x 10(-3). We also measure parameters of two K(L)gamma*gamma form factor models. In the Bergström-Massó-Singer parametrization, we find Calpha(K*)= -0.517 +/- 0.030(stat) +/- 0.022(syst). We separately fit for the first parameter of the D'Ambrosio-Isidori-Portolés model and find alpha(DIP)= -1.729 +/- 0.043(stat) +/- 0.028(syst).
Abouzaid
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The Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637, USA.
Arenton
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Barker
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Bellantoni
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Blucher
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Bock
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Cheu
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Coleman
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Corcoran
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Cox
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Erwin
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Glazov
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Golossanov
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Hsiung
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Jensen
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Kessler
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Kobrak
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Kotera
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LaDue
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Ledovskoy
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McBride
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Monnier
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Nguyen
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Niclasen
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Ramberg
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Ray
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Ronquest
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Shields
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Slater
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Smith
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Solomey
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Swallow
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Toale
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Tschirhart
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Wah
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Wang
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White
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Whitmore
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Wilking
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Winston
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Worcester
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Yamanaka
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Zimmerman
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