  We describe an experimental search for deviations from the inverse square law
of gravity at the nanometer length scale using neutron scattering from noble
gases on a pulsed slow neutron beamline. By measuring the neutron momentum
transfer ($q$) dependence of the differential cross section for xenon and
helium and comparing to their well-known analytical forms, we place an upper
bound on the strength of a new interaction as a function of interaction length
$\lambda$ which improves upon previous results in the region $\lambda <
0.1\,$nm, and remains competitive in the larger $\lambda$ region. A
pseudoexperimental simulation developed for this experiment and its role in the
data analysis described. We conclude with plans for improving sensitivity in
the larger $\lambda$ region.
