We have studied low-frequency (45 - 410 MHz) type III solar radio bursts observed using the e-CALLISTO spectrometer located at Gauribidanur radio observatory, India during 2013 - 2017. After inspecting the 1531 type III bursts we found that 426 bursts were associated with flares, while the other bursts might have triggered by small scale features / weak energy events present in the solar corona. In this study, we have carried out a statistical analysis of various observational parameters like start time, lower and upper-frequency cut-offs of type III bursts and their association with flares, variation of such parameters with flare parameters such as location, class, onset and peak timings. From this study, we found that most of the high-frequency bursts (whose upper-frequency cut-off $> 350$ MHz) are originated from the western longitudes. We interpret that it could be due to the fact that Parker spirals from these longitudes are directed towards the earth and high-frequency bursts are more directive. Further, we report that number of bursts that reach earth from western longitudes are higher than eastern longitudes.

中文翻译：

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低频太阳射电III型爆发的统计研究

我们研究了 2013 年至 2017 年期间使用位于印度 Gauribidanur 射电天文台的 e-CALLISTO 光谱仪观测到的低频（45 - 410 MHz）III 型太阳射电爆发。在检查了 1531 次 III 型爆发后，我们发现有 426 次爆发相关与耀斑，而其他爆发可能是由太阳日冕中存在的小规模特征/弱能量事件触发的。在这项研究中，我们对各种观测参数进行了统计分析，例如 III 型爆发的开始时间、下限和上限频率截止及其与耀斑的关联、这些参数与耀斑参数（例如位置、类别、发病和高峰时间。从这项研究中，我们发现大多数高频爆发（其上限频率 $> 350 $ MHz）起源于西经。我们解释这可能是由于这些经度的帕克螺旋是指向地球的，而高频爆发更具方向性。此外，我们报告说，从西经到达地球的爆发次数高于东经。