Collisions between asymmetric porous aggregates

PLANES, MARÍA BELÉN

Pasadena, California

Workshop; 2021 Sagan Exoplanet Summer Workshop on "Circumstellar Disks and Young Planets"; 2021

NASA Exoplanet Science Institute

It is currently not well known how planets formin their early stages. In protoplanetary discs, collisions betweenmicron-sized aggregates may lead to the build-up of increasinglylarger aggregates (intermediates in the building of planets).In suchcollisions, the main issue is whether they lead to aggregate growthor fragmentation. Using the MDpackage LAMMPS, we simulate asymmetric collisions between porousaggregates compoused by equal-size spherical silica grains (radius =0.76 μm).Our model incorporate friction forces between grains and isdetailed in [1]. Wevary: the impact velocity v, the mass ratio target/projectile, μ andtheir filling factor, φ (φ= 1-porosity). Our results show how the different initialparameters (porosity, collision velocity and mass ratio) are relevantin the main question:Will the aggregates stick together, or will theydestroy each other as a consequence of the collision?Analysis in ourworks would give clues about how planetesimals are formed inprotoplanetary discs.p { margin-bottom: 0.25cm; line-height: 115% }p { margin-bottom: 0.25cm; line-height: 115% } p { margin-bottom: 0.25cm; line-height: 115% }p { margin-bottom: 0.25cm; line-height: 115% }