Invited Presentation

Magnetic Fields in Massive Star-forming Regions (MagMaR)

Author(s): P. Saha (NAOJ) J. M. Girart (IEEC) P. Cortes (NRAO/JAO) M. Fernandez-Lopez (CCT-La Plata) Y.-W. Tang (ASIAA) P. Kock (ASIAA) L. Zapata (UNAM) F. Nakamura (NAOJ) F. Olguin (NTHU) Q. Zhang (CfA) H.-R. V. Chen (NTHU)

Presenter: Patricio Sanhueza (NAOJ)

The importance of magnetic fields (B-fields) in the high-mass star-forming process is a long-standing question. Indeed, several observational properties in high-mass star-forming regions (e.g., high/low level of core fragmentation, virial equilibrium) are frequently "explained" invoking B-fields, despite the lack of direct evidence of their presence or their importance with respect to turbulence and gravity. Some effort has been attempted to address the importance of B-fields by observing statistically significant samples, for example, with SMA and CARMA, but not so far with ALMA. Here, we introduce the first ALMA survey, Magnetic Fields in Massive Star-forming Regions (MagMaR). In MagMaR, 30 high-mass star-forming regions have been observed at 1.2 mm, resulting in ~0.3" resolution (~1000 au). A large variety of B-field morphologies is detected: (1) "simple" spiral- or hourglass-like, that are dominated by a single, bright continuum source; (2) filamentary, with B-field vectors sometimes parallel to the elongated dust emission and characterized with aligned fragmentation; (3) complex B-field morphology with highly clustered fragmentation. We will discuss the initial findings of the survey and present results of some case studies including dust and line polarization.