INVESTIGADORES
DE FLORIAN daniel Enrique
artículos
Título:
The Triple Collinear limit of one-loop QCD amplitudes
Autor/es:
DANIEL DE FLORIAN; STEFANO CATANI; GERMAN RODRIGO
Revista:
PHYSICS LETTERS B
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2004 vol. 586 p. 323 - 323
ISSN:
0370-2693
Resumen:
We consider the singular behaviour of one-loop QCD matrix elements when several external partons become simultaneously parallel. We present a new factorization formula that describes the singular collinear behaviour directly in colour space. The collinear singularities are embodied in process-independent splitting matrices that depend on the momenta, flavours, spins and colours of the collinear partons. We give the general structure of the infrared and ultraviolet divergences of the one-loop splitting matrices. We also present explicit one-loop results for the triple collinear splitting, q->q ar{Q}Q, of a quark and a quark–antiquark pair of different flavours. The one-loop triple collinear splitting is one of the ingredients that can be used to compute the evolution of parton distributions at the next-to-next-to-leading order in QCD perturbation theory.