The Great Attractor and the Shapley Concentration
  We develop a non-linear relativistic model of the Shapley Concentration (SC) and its environs, including the Great Attractor (GA) and the Local Group (LG). We take the Shapley concentration as a major attractive centre, and we use the Lemaitre-Tolman model. We constrain our model with present day observations, plus the requirement that it have a physically reasonable evolution from small perturbations at last scattering. We investigate possible mass and velocity distributions, and we find that the peculiar velocity maximum near the SC is \~800 km/s inwards, the density between GA and SC must be about ~0.9 times background, the mass of the GA is probably 4 - 6 x 10^15 M_sun, the SC's contribution to the LG motion is negligible, and the value of the cosmological constant is not significant on this scale. 
Krzysztof Bolejko and Charles Hellaby