@article{10272/18415,
year = {2008},
month = {6},
url = {http://hdl.handle.net/10272/18415},
abstract = {We solve numerically the Schwinger-Dyson ghost equation in the Landau gauge
for a given, finite at k = 0 gluon propagator (i.e. the infrared exponent of its dressing
function, αgluon, is 1) and under the usual assumption of constancy of the ghost-gluon
vertex ; we show that there exist two possible types of ghost dressing function solutions,
as we have previously inferred from analytical considerations: one which is singular at zero
momentum (the infrared exponent of its dressing function, αghost,† is < 0), satisfies the
familiar relation αgluon + 2αghost = 0 and has therefore αghost = −1/2, and another one
which is finite at the origin with αghost = 0 and violates the relation. It is most important
that the type of solution which is realized depends on the value of the coupling constant.
There are regular ones — αF = 0 — for any coupling below some value, while there is only
one singular solution — αF < 0 —, obtained for a single critical value of the coupling. For
all momenta k < 1.5GeV where they can be trusted, our lattice data exclude neatly the
singular one, and agree very well with the regular solution we obtain at a coupling constant
compatible with the bare lattice value.},
publisher = {Springer Verlag},
title = {IR finiteness of the ghost dressing function from numerical resolution of the ghost SD equation},
doi = {10.1088/1126-6708/2008/06/012},
author = {Boucaud, Ph. and Leroy, J. P. and Le Yaouanc, Alain and Micheli, J. and Pène, O. and Rodríguez Quintero, José},
}