Tracking a beam of electrons from the low solar corona into interplanetary space with the Low Frequency Array, Parker Solar Probe and 1 au spacecraft

Abstract

Type III radio bursts are the result of plasma emission from mildly relativistic electron beams propagating from the low solar corona into the heliosphere where they can eventually be detected in situ if they align with the location of a heliospheric spacecraft. Here we observe a type III radio burst from 0.1-16 MHz using the Parker Solar Probe (PSP) FIELDS Radio Frequency Spectrometer (RFS), and from 20-80 MHz using the Low Frequency Array (LOFAR). This event was not associated with any detectable flare activity but was part of an ongoing type III and noise storm that occurred during PSP encounter 2. A deprojection of the LOFAR radio sources into 3D space shows that the type III radio burst sources were located on open magnetic field from 1.6-3 R${}_{\odot }$ and originated from a near-equatorial active region around longitude E48${}^o$. Combining PSP/RFS observations with WIND/WAVES and STEREO/WAVES, we reconstruct the type III radio source trajectory in the heliosphere interior to PSP's position, assuming ecliptic confinement. An energetic electron enhancement is subsequently detected in situ at the STEREO-A spacecraft at compatible times although the onset and duration suggests the individual burst contributes a subset of the enhancement. This work shows relatively small-scale flux emergence in the corona can cause the injection of electron beams from the low corona into the heliosphere, without needing a strong solar flare. The complementary nature of combined ground and space-based radio observations, especially in the era of PSP, is also clearly highlighted by this study.

16 pages, 11 figures, Submitted to ApJ: April 15 2022, Accepted: September 7 2022

References in corpus (12)

• The Solar Orbiter mission -- Science overview
• WSClean: an implementation of a fast, generic wide-field imager for radio astronomy
• A Review of Solar Type III Radio Bursts
• Coherent Emission Mechanisms in Astrophysical Plasmas
• First in-situ Measurements of Electron Density and Temperature from Quasi-Thermal Noise Spectroscopy with Parker Solar Probe/FIELDS
• Switchbacks Explained: Super-Parker Fields -- the Other Side of the Sub-Parker Spiral
• Density Fluctuations in the Solar Wind Based on Type III Radio Bursts Observed by Parker Solar Probe
• Statistics and Polarization of Type III Radio Bursts Observed in the Inner Heliosphere
• Fine structure of type III solar radio bursts from Langmuir wave motion in turbulent plasma
• Simulations of radio-wave anisotropic scattering to interpret type III radio bursts measurements by Solar Orbiter, Parker Solar Probe, STEREO and Wind
• Using radio triangulation to understand the origin of two subsequent type II radio bursts
• The active region source of a type III radio storm observed by Parker Solar Probe during Encounter 2

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• Solar energetic particles injected inside and outside a magnetic cloud: The widespread solar energetic particle event on 2022 January 20
• Tracking solar radio bursts using Bayesian multilateration
• Electron Beam Propagation and Radio-Wave Scattering in the Inner Heliosphere using Five Spacecraft
• Electromagnetic radiation by turbulent, magnetized and randomly inhomogeneous solar radio sources generated by electron beams
• Coronal Diagnostics of Solar Type-III Radio Bursts Using LOFAR and PSP Observations
• Coronal electron density: Insights from radio and in situ observations, and EUHFORIA modeling
• Single-Mode Wave Decay