Antenna subtraction with massive fermions at NNLO: Double real   initial-final configurations
  We derive the integrated forms of specific initial-final tree-level four-parton antenna functions involving a massless initial-state parton and a massive final-state fermion as hard radiators. These antennae are needed in the subtraction terms required to evaluate the double real corrections to $t\bar{t}$ hadronic production at the NNLO level stemming from the partonic processes $q\bar{q}\to t\bar{t}q'\bar{q}'$ and $gg\to t\bar{t}q\bar{q}$. 
Gabriel Abelof (1), Aude Gehrmann-De Ridder (1), Oliver Dekkers (2)   ((1) Institute for Theoretical Physics, ETH Z\"urich, ...
hep-ph