3D-modelling of the stellar auroral radio emission

TL;DR

This paper introduces a 3D model for simulating auroral radio emissions from magnetized stars, helping to understand pulse timing, profiles, and detectability of such coherent emissions.

Contribution

It presents a novel tridimensional model based on the laminar source hypothesis to simulate stellar auroral radio pulses, advancing understanding of their characteristics and detectability.

Findings

The model effectively reproduces pulse timing and profiles.

Free parameters significantly influence pulse features.

The model aids in assessing the detectability of stellar auroral radio emissions.

Abstract

The electron cyclotron maser is the coherent emission process that gives rise to the radio lighthouse effect observed in the hot magnetic chemically peculiar star CU Virginis. It has also been proposed to explain the highly circularly polarized radio pulses observed on some ultra cool dwarfs, with spectral type earlier than M7. Such kind of coherent events resemble the auroral radio emission from the magnetized planets of the solar system. In this paper, we present a tridimensional model able to simulate the timing and profile of the pulses emitted by those stars characterized by a dipolar magnetic field by following the hypothesis of the laminar source model, used to explain the beaming of the terrestrial auroral kilometric radiation. This model proves to be a powerful tool to understand the auroral radio-emission phenomenon, allowing us to derive some general conclusions about the effects of the model's free parameters on the features of the coherent pulses, and to learn more about the detectability of such kind of pulsed radio emission.