https://doi.org/10.1140/epjc/s2006-02583-9
Theoretical Physics
The two-loop vector form factor in the Sudakov limit
1
Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
2
Institut für Theoretische Teilchenphysik, Universität Karlsruhe, 76128, Karlsruhe, Germany
3
Nuclear Physics Institute, Moscow State University, 119992, Moscow, Russia
4
II. Institut für Theoretische Physik, Universität Hamburg, 22761, Hamburg, Germany
* e-mail: physics@bernd-jantzen.de
Received:
20
March
2006
Revised:
24
April
2006
Published online:
27
June
2006
Recently two-loop electroweak corrections to the neutral current four-fermion processes at high energies have been presented. The basic ingredient of this calculation is the evaluation of the two-loop corrections to the Abelian vector form factor in a spontaneously broken SU(2) gauge model. Whereas the final result and the derivation of the four-fermion cross sections from evolution equations have been published earlier, the calculation of the form factor from the two-loop Feynman diagrams is presented for the first time in this paper. We describe in detail the individual contributions to the form factor and their calculation with the help of the expansion by regions method and Mellin–Barnes representations.
© Springer-Verlag, 2006