  Many physics analyses at the LHC are looking into processes where the signal
jets are originating from quarks, while jets in the background are more gluon
enriched. Based on observables sensitive to fundamental differences in the
fragmentation properties of gluons and quarks, a likelihood discriminant is
constructed to distinguish between jets originating from quarks and gluons. The
performance of the tagger is evaluated using Z+jets and dijet events produced
in proton-proton collisions at a centre-of-mass energy of 8 TeV, recorded by
the CMS experiment at the LHC.
