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E. Abouzaid et al.

Publications and source records attributed to E. Abouzaid et al..

2 recordsLinked to original sources

arXiv2009

Dispersive analysis of K_{L mu3} and K_{L e3} scalar and vector form factors using KTeV data

Using the published KTeV samples of K_L --> pi^{\pm} e^{\mp} nu and K_L --> pi^{\pm} mu^{\mp} nu decays [1], we perform a reanalysis of the scalar and vector form factors based on the dispersive parameterization [2,3]. We obtain phase space integrals I^e_K = 0.15446 \pm 0.00025 and I^{mu}_K = 0.10219 \pm 0.00025. For the scalar form factor parameterization, the only free parameter is the normalized form factor value at the Callan-Treiman point (C); our best fit results in ln C = 0.1915 \pm 0.0122. We also study the sensitivity of C to different parametrizations of the vector form factor. The results for the phase space integrals and C are then used to make tests of the Standard Model. Finally, we compare our results with lattice QCD calculations of F_K/F_pi and f_+(0).

hep-ex↗

arXiv2007

Measurements of the Decay $K_L \to e^+e^-γ$

The E799-II (KTeV) experiment at Fermilab has collected 83262 $K_L \to e^+e^-γ$ events above a background of 79 events. We measure a decay width, normalized to the $K_L \to π^0π^0π^0_D$ (π^0 \to γγ, π^0 to γγ, π^0_D \to e^+e^-γ) decay width, of $Γ($K_L \to e^+e^-γ$)/Γ(K_L \to π^0π^0π^0_D) = (1.3302 \pm 0.0046_{stat} \pm 0.0102_{syst}) \times 10^{-3}$. We also measure parameters of two $K_L γ^{\ast}γ$ form factor models. In the Bergstrom, Masso, and Singer (BMS) parametrization, we find $\caks = -0.517 \pm 0.030_{stat} \pm 0.022_{syst}$. We separately fit for the first parameter of the D'Ambrosio, Isidori, and Portoles (DIP) model and find $\adip = -1.729 \pm 0.043_{stat} \pm 0.028_{syst}$.

hep-ex↗