  The spectrum of gluon excitations in the presence of a static quark-antiquark
pair is presented. Our results are obtained from computer simulations of gluons
on anisotropic space-time lattices using an improved gauge-field action.
Measurements for quark-antiquark separations r ranging from 0.1 fm to 4 fm and
for various orientations on the lattice are made. Discretization errors and
finite volume effects are taken into account. Surprisingly, the spectrum does
not exhibit the expected onset of the universal pi/r Goldstone excitations of
the effective QCD string, even for r as large as 4 fm.
