2 research outputs found
Polarized QED splittings of massive fermions and dipole subtraction for non-collinear-safe observables
Building on earlier work, the dipole subtraction formalism for photonic
corrections is extended to various photon--fermion splittings where the
resulting collinear singularities lead to corrections that are enhanced by
logarithms of small fermion masses. The difference to the earlier treatment of
photon radiation is that now no cancellation of final-state singularities is
assumed, i.e. we allow for non-collinear-safe final-state radiation. Moreover,
we consider collinear fermion production from incoming photons,
forward-scattering of incoming fermions, and collinearly produced
fermion-antifermion pairs. For all cases we also provide the corresponding
formulas for the phase-space slicing approach, and particle polarization is
supported for all relevant situations. A comparison of numerical results
obtained with the proposed subtraction procedure and the slicing method is
explicitly performed for the sample process e- gamma -> e- mu- mu+.Comment: 44 pages, late