Electroweak properties of the π, K and K*(892) in the three forms of relativistic kinematics

Abstract

The electromagnetic form factors, charge radii and decay constants of π, K and K*(892) are calculated using the three forms of relativistic kinematics: instant form, point form and (light) front form. Simple representations of the mass operator together with single-quark currents are employed with all the forms. Making use of previously fixed parameters, together with the constituent-quark mass for the strange quark, a reasonable reproduction of the available data for form factors, charge radii and decay constants of π, ρ, K and K*(892) is obtained in front form. With the instant form a similar description, but with a systematic underestimation of the vector meson decay constants is obtained using two different sets of parameters, one for π and ρ and another one for K and K*(892). The point form produces a poor description of the data.