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...
Ionization rate is one of the most important parameters controlling both the chemical and dynamical processes in protoplanetary disks. What few observational constrains on ionization currently exists suggest overall low ionization, limiting the processes able to take place. I will present new NOEMA observations which, when combined with chemical modeling, are indicative of enhanced ionization...
Surveys of protoplanetary disks in star-forming regions of similar age revealed
significant variations in average disk mass between some regions. Disks in the Orion Nebular Cluster (ONC) and Corona Australis (CrA) are on average a factor of a few smaller than disks observed in Lupus, Taurus, Chamaeleon I or Ophiuchus. We aim for an understanding of the physical mechanism behind this spread...
