论文标题
在黑子周期的降期间，“安静”电晕的低频无线电观察24
Low frequency radio observations of the `quiet' corona during the descending phase of sunspot cycle 24
论文作者
论文摘要
我们使用Gauribidanur RadioHeliograph（Graph）在53 MHz和80 MHz的同时使用Gauribidanur Radioheliograph（Graph）获得的数据，对24日周期的下降阶段（即2015年1月至2019年5月）进行了对“安静”太阳电晕的统计研究。我们的结果表明，在上述两个频率上，太阳能电晕的赤道（东西方）直径稳步缩小。发现减少是由于冠状电子密度逐渐降低（$ n_ {e} $）。使用白色轻冠观测的“背景”电晕赤道区域中$ n_ {e} $的独立估计表明，下降与我们的发现一致。
We carried out a statistical study of the `quiet' solar corona during the descending phase of the sunspot cycle 24 (i.e. 2015 January - 2019 May) using data obtained with the Gauribidanur RAdioheliograPH (GRAPH) at 53 MHz and 80 MHz simultaneously. Our results show that the equatorial (east-west) diameters of the solar corona at the above two frequencies shrunk steadily. The decrease was found to be due to a gradual reduction in the coronal electron density ($N_{e}$). Independent estimates of $N_{e}$ in the equatorial region of the `background' corona using white-light coronagraph observations indicate a decline consistent with our findings.
