期刊
ASTROPHYSICAL JOURNAL
卷 700, 期 1, 页码 251-261出版社
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/700/1/251
关键词
ISM: individual (W51 e2/e8); ISM: magnetic fields; polarization; stars: formation
资金
- National Science Council of Taiwan [NSC 97-2112-M-001-007-MY3]
We report our observational results of 870 mu m continuum emission and its linear polarization in the massive star formation site W51 e2/e8. Inferred from the linear polarization maps, the magnetic field in the plane of sky (B-perpendicular to) is traced with an angular resolution of 0 ''.7 with the Submillimeter Array. Whereas previous BIMA observations with an angular resolution of 3 '' (0.1 pc) showed a uniform B field, our revealed B-perpendicular to morphology is hourglass-like in the collapsing core near the ultracompact H II region e2 and also possibly in e8. The decrease in polarization near the continuum peak seen at lower angular resolution is apparently due to the more complex structures at smaller scales. In e2, the pinched direction of the hourglass-like B-field morphology is parallel to the plane of the ionized accretion flow traced by H53 alpha, suggesting that the massive stars are formed via processes similar to the low-mass stars, i.e., accretion through a disk, except that the mass involved is much larger. Furthermore, our finding that the resolved collapsing cores in e2 and e8 lie within one subcritical 0.5 pc envelope supports the scenario of magnetic fragmentation via ambipolar diffusion. We therefore suggest that magnetic fields control the dynamical evolution of the envelope and cores in W51 e2 and e8.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据