The Study of Coronal Plasma Turbulence with Radioastro- nomical Interferometers

该项目将利用无线电传播技术研究日冕和太阳风中的等离子体湍流。无线电波的来源是河外射电源，它在很宽的频率范围内发射部分线偏振辐射。用甚大阵(VLA)和甚长基线阵(VLBA)等标准射电天文仪器观测震源。当通过日冕和太阳风的湍流等离子体介质观察这些源时，可能会观察到各种扭曲或“模糊”效应。通过对这些效应的测量，可以推断出关于湍流的强度、空间功率谱和物理性质的信息。在拟议的授权期内，将通过两种类型的观测获得有关日冕湍流的信息。第一种是测量通过湍流介质观察到的射电信号源的角度加宽或“模糊”。这些观测将与VLA和VLBA一起进行。第二类观测包括测量早偏振射电源偏振面的法拉第旋转。这些观测将与VLA一起进行，并将提供有关日冕中磁场变化以及密度变化的信息。最后，将进行将射电天文观测数据与日冕等离子体波特性联系起来的理论工作。#

This project will study plasma turbulance in the solar corona and solar wind using radio propagation techniques. The sources of the radio waves are extragalactic radio sources which emit partially linearly polarized radiation over a wide frequency range. The sources are observed with standard radioastronomical instruments such as the Very Large Array (VLA) and Very Long Baseline Array (VLBA). When these sources are viewed through the turbulent plasma medium of the corona and solar wind, various distortion or "blurring" effects may be observed. From measurements of these effects, information about the intensity, spatial power spectrum, and physical nature of the turbulence can be deduced. During the proposed grant period information on coronal turbulence will be obtained from two types of observation. The first is a measurement of angular broadening or "blurring" of a radio source viewed through a turbulent medium. These observations will be carried out with the VLA and VLBA. The second type of observation consists of measurement of Faraday Rotation of the plane of polarization of alinearly polarized radio source. These observations will be made with the VLA and will provide information on variations in the magnetic field in the corona as well as density variations. Finally, theoretical work will be made which relates radioastronomical observables to properties of coronal plasma waves. #