Analysis of the vector form factors f(K pi)(+)(Q(2)) and f(K pi)(-)(Q(2)) with light-cone QCD sum rules

作者：Wang Zhi Gang^*; Wan Shao Long

来源：European Physical Journal C, 2007, 50(4): 781-791.

DOI：10.1140/epjc/s10052-007-0249-z

In this article, we calculate the vector form factors f(K pi)(+)(Q(2)) and f(K pi)(-)(Q(2)) within the framework of the light-cone QCD sum rule approach. The numerical values of f(K pi)(+)(Q(2)) are compatible with existing theoretical calculations, and the central value of f(K pi)(+)(0) (f(K pi)(+)(0) = 0.97) is in excellent agreement with the values from chiral perturbation theory and lattice QCD. The values of vertical bar f(K pi)(-)(0)vertical bar are very large compared to the theoretical calculations and experimental data, and they cannot give any reliable prediction. At large momentumtransfer with Q(2) > 5GeV(2), the form factors f(K pi)(+)(Q(2)) and vertical bar f(K pi)(-)(Q(2))vertical bar can either show the asymptotic behavior of 1/Q(2) or decrease more quickly than 1/Q(2); more experimental data are needed to select the ideal sum rules.

• 出版日期2007-5
• 单位华北电力大学