Tracking solar radio bursts using Bayesian multilateration

Abstract

Solar radio bursts (SRBs), are emitted by electrons propagating through the corona and interplanetary space. Tracking such bursts is key to understanding the properties of accelerated electrons and radio wave propagation as well as the local plasma environment that they propagate through. Here, we present a novel multilateration algorithm called BayEsian LocaLisation Algorithm (BELLA). In addition, apparent SRB positions from BELLA are compared with comparable localisation methods and the predictions of solar wind models. BELLA uses Bayesian inference to create probabilistic distributions of source positions and their uncertainties. This facilitates the estimation of algorithmic, instrumental, and physical uncertainties in a quantitative manner. We validated BELLA using simulations and a Type III SRB observed by STEREO A/B and Wind. BELLA tracked the Type III source from $\sim$ 10--150 $R_{sun}$ (2-0.15 MHz) along a spiral trajectory. This allowed for an estimate of an apparent solar wind speed of $v_{sw}\sim$ 400 km s${}^{-1}$ and a source longitude of ${\varphi }_0\sim$ 30deg. We compared these results with well-established methods of positioning: Goniopolarimetric (GP), analytical time-difference-of-arrival (TDOA), and Solar radio burst Electron Motion Tracker (SEMP). We found them to be in agreement with the results obtained by BELLA. Additionally, the results aligned with solar wind properties assimilated by the Heliospheric Upwind Extrapolation with time dependence (HUXt) model. We have validated BELLA and used it to identify apparent source positions as well as velocities and densities of the solar wind. Furthermore, we identified higher than expected electron densities, suggesting that the true emission sources were at lower altitudes than those identified by BELLA, an effect that may be due to appreciable scattering of electromagnetic waves by electrons in interplanetary space.

arXiv comment13 pages, 12 figures, in press, accepted by Astronomy and Astrophysics for publication

References in corpus (15)

• LOFAR: The LOw-Frequency ARray
• The Solar Orbiter mission -- Science overview
• A Review of Solar Type III Radio Bursts
• Anisotropic Radio-Wave Scattering and the Interpretation of Solar Radio Emission Observations
• LOFAR tied-array imaging of Type III solar radio bursts
• Automated Coronal Hole Identification via Multi-Thermal Intensity Segmentation
• A variational approach to Data Assimilation in the Solar Wind
• An Anisotropic Density Turbulence Model from the Sun to 1 au Derived From Radio Observations
• Improving solar wind forecasting using Data Assimilation
• 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
• LOFAR observations of a jet-driven piston shock in the low solar corona
• 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
• Source positions of an interplanetary type III radio burst and anisotropic radio-wave scattering
• Forward Modeling of the Type III Radio Burst Exciter

Cited by in corpus (2)

• Electron Beam Propagation and Radio-Wave Scattering in the Inner Heliosphere using Five Spacecraft
• Coronal electron density: Insights from radio and in situ observations, and EUHFORIA modeling