ALMA news on magnetic fields threading low mass star forming Polarization Archetypes in Protostellar Disks Josep-Miquel Girart ICE, Barcelona, CT
Part 1: Here we present polarimetric ALMA observations towards low mass protostellar YSOs. Surprisingly, the studied YSOs show very different magnetic field properties, which may point to different initial conditions. Nevertheless, in some cases we find that the polarization appears to be enhanced along the outflow cavities, which reinforces the idea that dust grain alignment with magnetic fields is produced by RATS, Part 2: Linear polarization observations with ALMA is allowing to study the dust polarization properties at disk scales. Contrary to what it was though few years ago, the dust polarized emission in protostellar disks is not only produced by dust grains aligned with the magnetic fields. Self-scattering and radiative flux RATS of large grains can contribute significantly to the polarized emission. In this presentation we will show different targets where the different mechanism are revealed.
Caption: Color image of the polarization fraction (in %) overlapped with the contour image of the total dust emission and with the polarization "vectors" in the disk around a massive young stellar object. This image show two different polarization patterns, one from the inner disk and he other from the outer disk.
Collaborators: F. Alves, MPE, GE G. Anglada, IAA, ES F. Bacciotti, INAF, IT C. Carrasco-Gonzalez, IRyA, MX S. Curiel, IAA, MX G. Franco, UMG, BR M. Padovani, INAF, IT L. Podio, INAF, IT	Suggested Session: Protostellar disks