A Covariant Method for Calculating Helicity Amplitudes

Abstract

We present an alternative approach for calculating helicity amplitudes for processes involving both massless and massive fermions. With this method one can easily obtain covariant expressions for the helicity amplitudes. The final expressions involve only four vector products and are independent of the basis for gamma matrices or specific form of the spinors. We use the method to obtain the helicity amplitudes for several processes involving top quark production.

17 pages, 2 postscript figures, uses Latex2e and associated macros. Tex and Postcript files available via anonymous ftp at ftp://smuphy.physics.smu.edu/pub/vega/ , get hel*.*

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• A New Method for Helicity Calculations
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