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arXiv · 2309.05763

Fundamental-harmonic pairs of interplanetary type III radio bursts

Immanuel Christopher Jebaraj·Vladimir Krasnoselskikh·Marc Pulupa·Jasmina Magdalenic·Stuart Bale
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Abstract

Type III radio bursts are not only the most intense but also the most frequently observed solar radio bursts. However, a number of their defining features remain poorly understood. Observational limitations, such as a lack of sufficient spectral and temporal resolution, have hindered a full comprehension of the emission process, especially in the hecto-kilometric wavelengths. Of particular difficulty is the ability to detect the harmonics of type III radio bursts. Hereafter we report for the first detailed observations of type III fundamental-harmonic pairs in the hecto-kilometric wavelengths, observed by the Parker Solar Probe. We present the statistical analysis of spectral characteristics and the polarization measurements of the fundamental-harmonic pairs. Additionally, we quantify various characteristic of the fundamental-harmonic pairs, such as the time-delay and time-profile asymmetry. Our report and preliminary analysis conclude that fundamental-harmonic pairs constitute a majority of all type III radio bursts observed during close encounters 6 -- 10 when the probe is in close proximity to the source region and propagation effects are less pronounced.

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Immanuel Christopher Jebaraj, Vladimir Krasnoselskikh, Marc Pulupa, Jasmina Magdalenic, Stuart Bale. 2023-09-11. Fundamental-harmonic pairs of interplanetary type III radio bursts. https://arxiv.org/abs/2309.05763

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