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Formalism for dilepton production via virtual photon bremsstrahlung in hadronic reactions

Peter Lichard
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Abstract

We derive a set of new formulas for various distributions in dilepton production via virtual photon bremsstrahlung from pseudoscalar mesons and unpolarized spin-one-half fermions. These formulas correspond to the leading and sub-leading terms in the Low-Burnett-Kroll expansion for real photon bremsstrahlung. The relation of our leading-term formulas to previous works is also shown. Existing formulas are examined in the light of Lorentz covariance and gauge invariance. Numerical comparison is made in a simple example, where an "exact" formula and real photon data exist. The results reveal large discrepancies among different bremsstrahlung formulas. Of all the leading-term bremsstrahlung formulas, the one derived in this work agrees best with the exact formula. The issues of M_T-scaling and event generators are also addressed.

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Peter Lichard. 1998-12-01. Formalism for dilepton production via virtual photon bremsstrahlung in hadronic reactions. https://doi.org/10.1103/physrevd.51.6017

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