Kinematical Constraints of He Licity Amplitudes
نویسنده
چکیده
The kinematical constraints of helicity amplitudes are studied using the general ideas of Jackson and Hite. The helicity amplitudes are expressed in terms of a Taylor ser ies expansion from which all constraints at threshold and pseudothreshold can be tr ivial ly found. The simplicity of this approach is i l lustrated by deriving all of the constraints for 7rp --* N~ and ~rp --* AN.
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