Dynamical and collisional evolution of Kuiper belt binaries

ZANARDI MACARENA; BRUNINI ADRIÁN

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2016 vol. 455 p. 4487 - 4497

0035-8711

We present numerical simulations of the evolution of synthetic transneptunian binaries (TNBs) under the influence of the solar perturbation, tidal friction, and collisions with the population of classical Kuiper belt objects (KBOs). We show that these effects, acting together, have strongly sculpted the primordial population of TNBs. If the population of classical KBOs have a power-law size distribution as the ones that are inferred from recent observational surveys, the fraction of surviving binaries at present would be ∼70 per cent of the primordial population. The orbits of the surviving synthetic systems match reasonably well the observed sample. The collisional process excites the mutual orbital eccentricity of the binaries, acting against the effect of tides. Therefore only ∼10 per cent of the objects reach total orbital circularization (e ≤ 10−4). In addition, our results predict that the population of contact binaries in the transneptunian region should be small. Ultrawide binaries are naturally obtained by the combined action of Kozai cycles and tidal friction and collisional evolution, being the number and orbital distribution of them very similar to the ones of the observed population.