  We study how the successive scattering of spin 1/2 particles with a central
spin 1/2 target particle can generate entanglement between the helicity degrees
of freedom of all scattered particles, effectively producing a multipartite
entangled state. We show that the bipartite entanglement between each pair of
scattered particles, as quantified by the concurrence, is largest for reflected
particles and decreases with the number of scatterings. We study the
entanglement generation as a function of the scattered particles momenta,
angular distribution and mass ratios, and show that there is always a
combination of optimal helicities and momentum which generate the largest
amount of bipartite entanglement.
