A predictive framework for realistic star planet radio emission in compact systems

TL;DR

This study develops a simulation-based framework combining stellar wind models and magnetic data to prioritize star-planet systems for detecting radio emissions caused by magnetic interactions, aiding future observational efforts.

Contribution

It introduces a novel, data-driven method integrating ZDI maps, 3D MHD simulations, and emission modeling to identify promising targets for SPI radio detection.

Findings

Framework successfully applied to benchmark systems like Tau Boo and HD 179949.

Method estimates radio emission frequencies and powers, guiding observational strategies.

Potential to enhance detection prospects with improved magnetic and wind data.

Abstract

Radio emission from star planet interactions (SPI) beyond our solar system has yet to be firmly detected, primarily due to challenges such as weak signals, directional beaming effects, and low frequency emissions that are blocked by the ionosphere of Earth. Addressing these obstacles calls for strategic target selection. This proof of concept study aims to improve SPI target prioritization by simulating SPI induced radio emission frequencies and estimating associated radio power to identify systems most likely to produce detectable signals. We combine Zeeman Doppler Imaging (ZDI) maps with 3D magnetohydrodynamic (MHD) stellar wind simulations and use the ExPRES code to model SPI driven radio emissions. We also estimate the intensity of these emissions using the Radio Magnetic Scaling Law, based on the magnetic field and plasma density parameters from the 3D wind models. This approach is applied to systems such as Tau Boo, HD 179949, and HD 189733 to assess their detectability with current and future radio telescopes. This framework, tested on benchmark systems, is applicable to any star planet system with available ZDI maps and wind models. As magnetic field reconstructions and wind simulations improve, the method will become more robust. It provides a data driven approach to prioritize targets and optimize telescope scheduling. This shall enable systematic exploration of magnetic SPI radio emissions across a wide range of exoplanetary systems.