Thinkshop 2020

Magnetic fields play a major role in the regulation of angular momentum during the protostellar collapse, hence for the formation of the protoplanetary disk. The magnetic braking is able to slow the rotation and extract the angular momentum from the disk. However, this process is tampered by a decoupling between neutral and charged particles, especially the ions through the ambipolar diffusion. The decoupling is heavily impacted by the chemistry at stake, and particularly by the grain size distribution. I will show how a modification of the grain size distribution enhances the decoupling between the magnetic field and the gas, and how it modifies the distribution and transport of angular momentum.