Measurements of the Branching Fractions and Decay Distributions for KL->πμνγand KL->πeνγ

T. Alexopoulos; T. Andre; M. Arenton; R. F. Barbosa; A. R. Barker; L. Bellantoni; A. Bellavance; E. Blucher; G. J. Bock; E. Cheu; S. Childress; R. Coleman; M. D. Corcoran; B. Cox; A. R. Erwin; R. Ford; A. Glazov; A. Golossanov; J. Graham; J. Hamm; K. Hanagaki; Y. B. Hsiung; H. Huang; V. Jejer; D. A. Jensen; R. Kessler; H. G. E. Kobrak; K. Kotera; J. LaDue; A. Ledovskoy; P. L. McBride; E. Monnier; K. S. Nelson; H. Nguyen; R. Niclasen; V. Prasad; X. R. Qi; E. J. Ramberg; R. E. Ray; M. Ronquest; E. Santos; P. Shanahan; J. Shields; W. Slater; D. Smith; N. Solomey; E. C. Swallow; P. A. Toale; R. Tschirhart; Y. W. Wah; J. Wang; H. B. White; J. Whitmore; M. Wilking; B. Winstein; R. Winston; E. T. Worcester; T. Yamanaka; E. D. Zimmerman

doi:10.1103/physrevd.71.012001

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Measurements of the Branching Fractions and Decay Distributions for KL->πμνγand KL->πeνγ

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Abstract

We present measurements of R_Kl3rad = Gamma(KL->π\ellνγ; Egcm > 10 MeV)/Gamma(KL->π\ellν), 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->πμνγand 14221 KL->π\eνγcandidates, 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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T. Alexopoulos, T. Andre, M. Arenton, R. F. Barbosa, A. R. Barker, L. Bellantoni, A. Bellavance, E. Blucher, G. J. Bock, E. Cheu, S. Childress, R. Coleman, M. D. Corcoran, B. Cox, A. R. Erwin, R. Ford, A. Glazov, A. Golossanov, J. Graham, J. Hamm, K. Hanagaki, Y. B. Hsiung, H. Huang, V. Jejer, D. A. Jensen, R. Kessler, H. G. E. Kobrak, K. Kotera, J. LaDue, A. Ledovskoy, P. L. McBride, E. Monnier, K. S. Nelson, H. Nguyen, R. Niclasen, V. Prasad, X. R. Qi, E. J. Ramberg, R. E. Ray, M. Ronquest, E. Santos, P. Shanahan, J. Shields, W. Slater, D. Smith, N. Solomey, E. C. Swallow, P. A. Toale, R. Tschirhart, Y. W. Wah, J. Wang, H. B. White, J. Whitmore, M. Wilking, B. Winstein, R. Winston, E. T. Worcester, T. Yamanaka, E. D. Zimmerman. 2004-10-23. Measurements of the Branching Fractions and Decay Distributions for KL->πμνγand KL->πeνγ. https://doi.org/10.1103/physrevd.71.012001

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