qq' -> qq': a second look at the IR divergences
Abstract
The transport properties of the quark-gluon plasma is important both from the point of view of the astrophysical systems and the heavy ion collisions. Therefore, accurate calculations of the elastic scattering cross-sections of $qq' \to qq'$ and $ q\qbar' \to q\qbar'$ processes are required. At the tree-diagram level exchange of massless gluons leads to divergent cross sections for such processes. An effective way to remove the infrared divergence is to introduce a Debye mass as an infrared regulator into the gluon propagator for the thermal gluons. In this work we find that at the two-gluon exchange level such a technique fails to remove the divergences. In a chiral symmetry broken phase the mass could be introduced following the standard procedure which cures the divergence. But in a chirally symmetric phase chiral invariant mass of the fermions needs to be considered.
- Publication:
-
arXiv e-prints
- Pub Date:
- June 1997
- DOI:
- 10.48550/arXiv.hep-ph/9706360
- arXiv:
- arXiv:hep-ph/9706360
- Bibcode:
- 1997hep.ph....6360K
- Keywords:
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- High Energy Physics - Phenomenology
- E-Print:
- 4 pages, latex, 1 figure