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تسجيل مستخدم جديدMeasurements of the Branching Fractions and Decay Distributions for KL->pimu ugamma and KL->pi e ugamma
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We present measurements of R_Kl3rad = Gamma(KL->piell ugamma; Egcm > 10 MeV)/Gamma(KL->piell u), where ell = mu or e, and Egcm is the photon energy in the kaon rest frame. These measurements are based on KL decays collected in 1997 by the KTeV (E832) experiment at Fermilab. With samples of 1385 KL->pimu ugamma and 14221 KL->pie ugamma candidates, we find R_Km3rad = (0.530 +- 0.019)% and R_Ke3rad = (4.942 +- 0.062)%. We also examine distributions of photon energy and lepton-photon angle.
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We present new results on the related rare KL decay modes KL -> pi+ pi- gamma and KL -> pi+ pi- e+ e-. KTeV has performed the first direct measurement of the form factor for the direct emission component of KL -> pi+ pi- gamma decays, a quantity with
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