EPoS Contribution
EPoS Contribution
Magnetic Fields at the Onset of High-Mass Star Formation

Henrik Beuther
MPIA, Heidelberg, DE
The properties of magnetic fields at the earliest stages of star formation are largely unexplored today. We present recent ALMA polarization observations toward the high-mass starless region IRDC18310-4 revealing the magnetic field properties toward this very young region. The polarized emission is clearly detected in four sub-cores. In general it shows a smooth distribution, also along elongated cores. Estimating the magnetic field strength via the Davis-Chandrasekhar-Fermi method, we find comparably large magnetic field strengths between 0.25 and 1.27mG. Comparing the data to spectral line observations, the turbulent-to-magnetic energy ratio is low, indicating that turbulence does not significantly contribute to the stability of the gas clump. A mass-to-flux ratio >=1 indicates that the region starts to collapse which is consistent with previous spectral line analysis of the region.
Suggested Session: Magnetic fields