2001/07/17 by Shih-Ping Lai, Shih‐Ping Lai, Richard M. Crutcher +2 · 4 citations
Physics and Astronomy · #Angular momentum #Astrophysics and Star Formation Studies #Circular polarization #Dust and Plasma Wave Phenomena #Interferometry #Linear polarization #Magnetic field #Optical properties and cooling technologies in crystalline materials #Polarization (electrochemistry) #Position angle #Wavelength #astro-ph
paper · pdf · doi:10.1086/323372
9 pages, 3 figures. Accepted for publication in the Astrophysical Journal, Nov 10, 2001 issue
arxiv created 2001/07/17 · openalex publication_date 2001/11/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present the first interferometric polarization map of the W51 e1/e2 molecular cores, obtained with the Berkeley-Illinois-Maryland Association (BIMA) array at 1.3 mm wavelength, with approximately 3'' resolution. The polarization angle varies smoothly across the double cores with an average position angle of 23° ± 5° for W51 e1 and 15° ± 7° for W51 e2. The inferred magnetic field direction is parallel to the minor axis of the double cores, which is consistent with the theoretical picture that clouds collapse along the field lines. However, the magnetic field may not determine the axis of angular momentum of these two cores, since the field directions of the two cores significantly differ from the previously measured directions of rotational axes. The polarization percentage decreases toward regions with high intensity, suggesting that the dust alignment efficiency decreases toward high-density regions. The field directions are highly ordered, and the small dispersion of the polarization angles implies that magnetic fields are strong (≳1 mG) and perhaps dominate turbulence in W51 e1/e2.