Conformation and topology of cyclical star polymers.

We study the conformation and topological properties of cyclical star polymers with f ring arms, each made of n beads. We find that the conformational properties of unlinked cyclical star polymers are compatible with those of linear star polymers with 2f arms made of n/2 beads each. This compatibility vanishes when the topology of the star, measured as the degree of linking between arms, changes. In fact, when links are allowed, we notice that the gyration radius decreases as a function of the absolute linking number |Lk| of the arms, regardless of the protocol that is employed to introduce said links. Furthermore, the internal structure of the macromolecules, as highlighted by the radial density function, changes qualitatively for large values of |Lk|.