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Title: Measurements of semileptonic K{sub L} decay form factors

Journal Article · · Physical Review. D, Particles Fields
;  [1]; ; ; ; ; ; ; ; ;  [2]; ; ; ; ; ; ; ; ;  [3]
  1. University of Wisconsin, Madison, Wisconsin 53706 (United States)
  2. Department of Physics and Institute of Nuclear and Particle Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)
  3. Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); and others

We present new measurements of K{sub L} semileptonic form factors using data collected in 1997 by the KTeV (E832) experiment at Fermilab. The measurements are based on 1.9x10{sup 6} K{sub L}{yields}{pi}{sup {+-}}e{sup {+-}}{nu} and 1.5x10{sup 6} K{sub L}{yields}{pi}{sup {+-}}{mu}{sup {+-}}{nu} decays. For f{sub +}(t), we measure both a linear and quadratic term: {lambda}{sub +}{sup '}=(20.64{+-}1.75)x10{sup -3} and {lambda}{sub +}{sup ''}=(3.20{+-}0.69)x10{sup -3}. For f{sub 0}(t), we find {lambda}{sub 0}=(13.72{+-}1.31)x10{sup -3}. These form factors are consistent with K{sup {+-}} form factors, suggesting that isospin symmetry breaking effects are small. We use our measured values of the form factors to evaluate the decay phase space integrals, I{sub K}{sup e}=0.15350{+-}0.00105 and I{sub K}{sup {mu}}=0.10165{+-}0.00080, where errors include uncertainties arising from the form factor parametrizations.

OSTI ID:
20705577
Journal Information:
Physical Review. D, Particles Fields, Vol. 70, Issue 9; Other Information: DOI: 10.1103/PhysRevD.70.092007; (c) 2004 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
Country of Publication:
United States
Language:
English