TY  - JOUR
AU  - Aguilar, A. C.
AU  - Binosi, D.
AU  - Papavassiliou, J.
PY  - 2010
DA  - 2010//
TI  - QCD effective charges from lattice data
T2  - J. High Energy Phys.
JO  - Journal of High Energy Physics
SP  - 002
EP  - 24pp
VL  - 07
IS  - 7
PB  - Springer
KW  - Nonperturbative Effects
KW  - QCD
AB  - We use recent lattice data on the gluon and ghost propagators, as well as the Kugo-Ojima function, in order to extract the non-perturbative behavior of two particular definitions of the QCD effective charge, one based on the pinch technique construction, and one obtained from the standard ghost-gluon vertex. The construction relies crucially on the definition of two dimensionful quantities, which are invariant under the renormalization group, and are built out of very particular combinations of the aforementioned Green's functions. The main non-perturbative feature of both effective charges, encoded in the infrared finiteness of the gluon propagator and ghost dressing function used in their definition, is the freezing at a common finite (non-vanishing) value, in agreement with a plethora of theoretical and phenomenological expectations. We discuss the sizable discrepancy between the freezing values obtained from the present lattice analysis and the corresponding estimates derived from several phenomenological studies, and attribute its origin to the difference in the gauges employed. A particular toy calculation suggests that the modifications induced to the non-perturbative gluon propagator by the gauge choice may indeed account for the observed deviation of the freezing values.
SN  - 1126-6708
UR  - http://arxiv.org/abs/1004.1105
UR  - https://doi.org/10.1007/JHEP07(2010)002
DO  - 10.1007/JHEP07(2010)002
LA  - English
N1  - ISI:000281504500002
ID  - Aguilar_etal2010
ER  -