  We investigate analytic classical solutions in open string field theory which
are constructed in terms of marginal operators. In the classical background, we
evaluate a coupling between an on-shell closed string state and the open string
field. The resulting coupling exhibits periodic behavior as expected from the
marginal boundary deformation of background Wilson lines or a marginal tachyon
lump. We confirm that the solutions in open string field theory correspond to a
class of marginal deformations in conformal field theory.

High Energy Physics - Theory