====== TTP08-15 Heavy-Flavor Contribution to Bhabha Scattering ======
 
 
<hidden TTP08-15  Heavy-Flavor Contribution to Bhabha Scattering > We evaluate the last missing piece of the two-loop QED corrections to the
 high-energy electron-positron scattering cross section originated from
 the vacuum polarization by heavy fermions.
 The calculation is performed within a new approach applicable
 to a wide class of perturbative problems with  mass hierarchy.
 The result is crucial  for the  high-precision physics program at existing
 and future $e^+e^-$ colliders.
 </hidden>
|**R. Bonciani, A. Ferroglia, A. A. Penin**  | 
|**  Phys.Rev.Lett.  100 131601 2008  **  |
| {{preprints:2008:ttp08-15.pdf|PDF}} {{preprints:2008:ttp08-15.ps|PostScript}}   |
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