Tomographic Imaging of the Velocity and Magnetic Fields in the Sun's Atmosphere

该提议是开发一种仪器，可以同时测量太阳大气中三个高度的声速和磁场。该仪器将使用调谐到422 nm(Ca1)、589 nm(NaD2)和770 nm(K)的太阳吸收线的磁光滤光片来测量多普勒速度和纵向磁场。这些线分别形成在中低色球层和光球层。此外，该仪器还将使用法布里-珀罗标准具作为窄带滤光器，测量在色球高层形成的1083 nm(He I)线的强度变化，该线显示日冕洞穴“脚点”的位置。这四条线加在一起，将可以研究整个太阳大气中的波动。该仪器将每10秒记录一次太阳图像，空间分辨率为1角秒。因此，该项目将把现有磁光滤光器技术的发展推向一个新的水平。建造完成后，该望远镜将在南极进行长时间的不间断观测。将利用当地和全球日震分析程序来确定和描述太阳大气中存在的不同类型的波。这些观测将允许通过地震测量确定太阳大气的结构和动力学，从而改进大气模型，评估波在加热色球/日冕和驱动太阳风方面的作用，并更好地了解太阳大气是如何耦合到太阳内部的。拟议项目的更广泛影响是两方面的。首先，这对科学和社会都有潜在的好处，因为人们认为太阳大气是许多现象的“家园”，这些现象可能会对太阳活动产生直接影响，包括耀斑、日冕物质抛射和太阳风。因此，了解太阳大气的结构和动力学将有助于更好地理解太阳与地球之间的联系。收集到的数据将提供给DVD的其他研究人员。更广泛的公众受众将通过在高中、图书馆和社区活动中的演讲以及在一般媒体上发表的新闻文章来接触到。大部分研究材料也将放在网上。

The proposal is to develop an instrument that can simultaneously measure the sound speed and magnetic fields at three heights in the solar atmosphere. The instrument will use magneto-optical filters tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), and 770 nm (K) to make measurements of Doppler velocities and longitudinal magnetic field. These lines form in the mid- and low-chromosphere and photosphere, respectively. In addition, the instrument will also use a Fabry-Perot etalon as a narrowband filter to measure the intensity variations of the 1083 nm (He I) line that is formed high in the chromosphere and which shows the location of the "foot points" of coronal holes. Together, the four lines will allow studying wave motions throughout the solar atmosphere. The instrument will record images of the Sun every 10 seconds with a spatial resolution of 1 arc-second. Thus, the project will be fostering the development of existing magneto-optical filter technology to a new level. Upon construction, the telescope will be tested at South Pole for a long period of uninterrupted observations. Both the local and global helioseismic analysis procedures will be utilized to identify and to characterize different types of waves present in the solar atmosphere. These observations will allow determining the structure and dynamics of the Sun's atmosphere through seismic measurements and, thus, improve the atmosphere models, assess the role of waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun's atmosphere couples to the interior. The broader impact of the proposed project is two fold. First, there is a potential benefit to the science and to the society because it is believed that the solar atmosphere is a "home" to many phenomena that can have a direct effect on the solar activity, including flares, coronal mass ejections, and the solar wind. Understanding the structure and dynamics of the solar atmosphere will therefore lead to a better understanding of the Sun-Earth connection. The collected data will be made available to other researchers at DVDs. The broader audience of general public will be reached through presentations at high schools, libraries, and community events, and news articles in the general press. Most of the research materials will also be placed in the Web.