  The centrality dependence of sqrt(s_NN)= 200 GeV d+Au {J/\psi} data, measured
in 12 rapidity bins that span -2.2 < y < 2.4, has been fitted using a model
containing an effective absorption cross section combined with EPS09 NLO
shadowing. The centrality dependence of the shadowing contribution was allowed
to vary nonlinearly, employing a variety of assumptions, in an effort to
explore the limits of what can be determined from the data. The impact
parameter dependencies of the effective absorption cross section and the
shadowing parameterization are sufficiently distinct to be determined
separately. It is found that the onset of shadowing is a highly nonlinear
function of impact parameter. The mid and backward rapidity absorption cross
sections are compared with lower energy data and, for times of 0.05 fm/c or
greater, data over a broad range of collision energies and rapidities are well
described by a model in which the absorption cross section depends only on time
spent in the nucleus.
