Evidence for magnetic-field-induced anisotropy of the interstellar medium
Evidence for magnetic-field-induced anisotropy of the interstellar medium
复制标题
磁场引起星际介质各向异性的证据
作者：
K. Desai;C. Gwinn;P. Diamond
星际介质中的湍流将能量从秒差距大小的区域转移到更小的尺度，并且可能是支撑云抵抗引力的原因。电子密度的起伏是湍流的痕迹，其尺度范围从106到> 1013 cm--这是在自然湍流中看到的最大的空间尺度范围。然而，尽管经过近三十年的研究，星际湍流的原因和影响仍然知之甚少。在这里，我们提出了在银河系恒星形成复合体W 49 N，我们使用的点源，调查散射沿着视线的OH脉泽的观测。脉泽的图像是椭圆形的，大致垂直于银河平面。这种排列表明，我们银河系的磁场通过调节能量从大到小的空间尺度的转移来影响星际的一致性。
TURBULENCE in the interstellar medium transfers energy from parsec-sized regions to much smaller scales, and may be respon-sible for supporting clouds against gravitational collapse1. Fluctua-tions in the electron density, which trace turbulence, occur on scales ranging from 106to >1013cm—the largest range of spatial scales seen in natural turbulence. Despite almost thirty years of study, however, the causes and effects of interstellar turbulence are still poorly understood. Here we present observations of OH masers in the Galactic star-forming complex W49N, which we use as point sources to investigate scattering along the line of sight. The masers' images are elliptical, and aligned roughly perpendicular to the Galactic plane. This alignment suggests that the magnetic field of our Galaxy influences interstellar turbulence2'3by mediating the transfer of energy from large to small spatial scales.