• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Astrophysical journal >HYDROGEN Lyα ABSORPTΘON PREDICTIONS BY BOLTZMANN MODELS OF THE HELIOSPHERE
【24h】

HYDROGEN Lyα ABSORPTΘON PREDICTIONS BY BOLTZMANN MODELS OF THE HELIOSPHERE

机译：球形球的Boltzmann模型预测氢Lyα吸附

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

We use self consistent kinetic/hydrodynamic models of the heliosphere to predict H I Lyα absorption profiles for various lines of sight through the heliosphere. These results are compared with Lya absorp- tion lines of six nearby stars observed by the Hubble Space Telescope. The directions of these lines of sight range from nearly upwind (36 Oph) to nearly downwind (∈ Eri). Only three of the Lyαspectra (36 Oph, a Cen, and Sirius) actually show evidence for the presence of heliospheric absorption, which is blended with the ubiquitous interstellar absorption, but the other three spectra still provide useful upper limits for the amount of heliospheric absorption for those lines of sight. Most of our models use a Bolt- zmann particle code for the neutrals, allowing us to estimate neutral velocity distributions throughout the heliosphere, from which we compute model Lyα absorption profiles. In comparing these models with the data, we find they predict too much absorption in sidewind and downwind directions, especially when higher Mach numbers are assumed for the interstellar wind. Models created assuming different values of the interstellar temperature and proton density fail to improve the agreement. Somewhat sur- prisingly, a model that uses a multifiuid treatment of the neutrals rather than the Boltzmann particle code is more consistent with the data, and we speculate as to why this may be the case.
机译：我们使用日球层的自洽动力学/流体动力学模型来预测通过日球层的各种视线的H ILyα吸收曲线。这些结果与哈勃太空望远镜观测到的六颗附近恒星的Lya吸收线进行了比较。这些视线的方向范围从近上风（36 Oph）到近下风（εEri）。 Lyα光谱中只有三个光谱（36 Oph，一个Cen和Sirius）实际上显示出存在日光层吸收的证据，该现象与无处不在的星际吸收混合在一起，但其他三个光谱仍然为日光层吸收量提供了有用的上限对于那些视线。我们的大多数模型对中性点使用Boltzmann粒子代码，这使我们能够估计整个太阳圈的中性速度分布，并据此计算模型Lyα吸收曲线。通过将这些模型与数据进行比较，我们发现它们预测了在侧风和顺风方向上的吸收过多，尤其是在假设星际风的马赫数更高的情况下。假设星际温度和质子密度不同的值创建的模型无法改善一致性。出乎意料的是，使用对中性点进行多流体处理而不是Boltzmann粒子代码的模型与数据更加一致，并且我们推测了为什么会这样。

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