• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Astrophysical journal >THE PROPERTIES OF MOLECULAR HYDROGEN TOWARD THE ORION BELT STARS FROM OBSERVATIONS BY THE INTERSTELLAR MEDIUM ABSORPTION PROFILE SPECTROGRAPH
【24h】

THE PROPERTIES OF MOLECULAR HYDROGEN TOWARD THE ORION BELT STARS FROM OBSERVATIONS BY THE INTERSTELLAR MEDIUM ABSORPTION PROFILE SPECTROGRAPH

机译：星际介质吸收谱图观测到的氢分子对猎户座带星的特性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Absorption features from the Lyman and Werner bands of interstellar molecular hydrogen were recorded by the Interstellar Medium Absorption Profile Spectrograph (IMAPS) at λ/Δλ = 80,000 in the spectra of δ Ori A and ε Ori. The objective was to find and study more examples of an unusual phenomenon found for one of the velocity components of H_2 in the spectrum of ζ Ori by Jenkins & Peimbert (1997). Specifically, they detected a gradual shift in velocity and broadening for features arising from progressively higher rotational excitations J. This effect appears to be absent in the spectra of both δ and ε Ori, which are only a few degrees away in the sky from ζ Ori. The absence of atomic material at a large negative velocity in the spectra of δ and ε Ori (and its presence in ζ Ori) supports a proposal by Jenkins & Peimbert that the line of sight to ζ intercepts a bow shock facing away from us, perhaps created by the collision of windlike material with some foreground obstruction. One edge of the molecular cloud complex Lynds 1630 is situated close to ζ Ori in the sky, but we present some evidence that seems to indicate that the cloud is more distant, in which case it could not serve as the obstruction. However, it is possible that the outermost extension of a high-speed jet from a star forming within the cloud can explain the high-velocity material and the shock front created by it. For both stars, the H_2 absorption features are separated into two velocity components. Total H_2 column densities toward δ and ε Ori are 5.5 x 10~(14) and 1.9 x 10~(16) cm~(-2), respectively. When these values are compared to the column densities of H Ⅰ, the fractions of H atoms bound in molecular form 2N(H_2)/[2N(H_2) + N(H Ⅰ)] = 7 x 10~(-6) for δ and 1.3 x 10~(-4) for ε. The rotation temperatures of the molecules with J > 2 toward e Ori indicate that the gas is in the general vicinity of the stars that emit UV fluxes capable of rotationally pumping the molecules. For the strongest component of H_2 toward δ Ori, the pumping rate is lower and consistent with a general UV flux level in the plane of the Galaxy.
机译：通过星际介质吸收分布谱仪（IMAPS）在δOri A和εOri的光谱中以λ/Δλ= 80,000记录了星际分子氢Lyman和Werner带的吸收特征。目的是发现和研究Jenkins＆Peimbert（1997）在ζOri谱中发现的H_2速度分量之一的异常现象的更多实例。具体来说，他们检测到速度逐渐移动并扩大了旋转激励J逐渐增大引起的特征。δ和εOri的光谱似乎都没有这种效应，它们在天空中与ζOri仅有几度的距离。 δ和εOri光谱中没有以大的负速度存在原子物质（以及它在ζOri中的存在），支持Jenkins＆Peimbert的建议，即ζ的视线拦截了背向我们的弓形冲击，也许由风状物质与某些前景障碍物碰撞而产生。分子云复合体Lynds 1630的一个边缘位于天空中靠近ζOri的位置，但是我们提供了一些证据，似乎表明该云距离更远，在这种情况下，它不能充当障碍物。但是，高速射流从云中形成的恒星的最外延伸可能可以解释高速物质和由其产生的激波锋。对于两个恒星，H_2吸收特征都分为两个速度分量。朝向δ和εOri的总H_2柱密度分别为5.5 x 10〜（14）和1.9 x 10〜（16）cm〜（-2）。将这些值与HⅠ的列密度进行比较时，对于δ，以分子形式2N（H_2）/ [2N（H_2）+ N（HⅠ）]结合的H原子分数= 7 x 10〜（-6） ε为1.3 x 10〜（-4）朝向e Ori的J> 2的分子的旋转温度表明，气体处于恒星的附近，这些恒星发出能够旋转泵浦分子的UV通量。对于H_2朝向δOri的最强成分，抽运速率较低，并且与银河系平面中的一般UV通量水平一致。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号