论文标题
在20-80 MHz的频率范围内安静的太阳的成像
Imaging of the Quiet Sun in the Frequency Range of 20-80 MHz
论文作者
论文摘要
安静的太阳的无线电排放被认为是由于热太阳大气的热bremsstrahlung发射。微波带中宁静的太阳的特性已经得到很好的研究，可以通过Bremsstrahlung发射的光谱来很好地描述它们。在仪表波和decameter波带中，由于仪器的限制，很少研究安静的太阳的特性。在这项工作中，我们使用低频阵列（Lofar）望远镜在90〜MHz以下的频率下对安静的太阳冠状发射进行高质量的干涉成像光谱观测。我们呈现亮度温度频谱和20-80〜MHz的频率范围内的太阳大小。我们报告亮度较低的深色冠状区域，该区域的频率持续存在。讨论了安静的太阳的亮度温度光谱，并将其与冠状模型的Bremsstrahlung发射和以前的安静太阳观测。
Radio emission of the quiet Sun is considered to be due to thermal bremsstrahlung emission of the hot solar atmosphere. The properties of the quiet Sun in the microwave band have been well studied, and they can be well described by the spectrum of bremsstrahlung emission. In the meter-wave and decameter-wave bands, properties of the quiet Sun have rarely been studied due to the instrumental limitations. In this work, we use the LOw Frequency ARray (LOFAR) telescope to perform high quality interferometric imaging spectroscopy observations of quiet Sun coronal emission at frequencies below 90~MHz. We present the brightness temperature spectrum, and size of the Sun in the frequency range of 20-80~MHz. We report on dark coronal regions with low brightness temperature that persist with frequency. The brightness temperature spectrum of the quiet Sun is discussed and compared with the bremsstrahlung emission of a coronal model and previous quiet Sun observations.
