Polarized Dust Emission in the Massive Protocluster W3 IRS5
Vivien Huei-Ru Chen1*, Qizhou Zhang2, Chat Hull2, Tao-Chung Ching1
1Institute of Astronomy, National Tsing Hua University, Hsinchu, Taiwan
2Center for Astrophysics, Harvard-Smithsonian, Cambridge, MA, United States of America
* presenting author:陳惠茹, email:hchen@phys.nthu.edu.tw
Polarized dust emission is often observed in star-forming cores to trace the morphology of magnetic fields. As part of the polarization legacy project with the Submillimeter Array, we have mapped the polarized dust emission in the nearby (1.95 kpc) massive protocluster W3 IRS5, where a small group of hyper-compact HII regions is forming in a compact core of size ~0.02 pc. Our 345 GHz observations achieved an angular resolution of ~2.5" and resolved the polarized dust emission into an hourglass morphology, indicating a pinched magnetic field geometry. Two pairs of outflows have been discovered, nearly perpendicular with each other. We will discuss the plausible configuration for the outflows, core rotation, and magnetic field morphology, as well as their implications to massive cluster formation.

Keywords: dust polarization, high-mass star formation