Solar Radio Imaging at Arecibo: The Brightness Temperature and Magnetic Field of Active Regions

TL;DR

This study demonstrates that regular X-band radio imaging with the Arecibo telescope can identify and track active solar regions, improving prediction of solar eruptions and space weather impacts by analyzing brightness temperature and magnetic properties.

Contribution

It introduces a novel method of solar mapping at X-band frequencies to predict active regions and solar eruptions with better accuracy than previous techniques.

Findings

Good correlation between brightness temperature evolution and magnetic configurations.

Mapping data improves understanding of active region formation and evolution.

Long-term X-band monitoring aids in predicting severe space weather events.

Abstract

Strong solar magnetic fields are the energy source of intense flares and energetic coronal mass ejections of space weather importance. The key issue is the difficulty in predicting the occurrence time and location of strong solar eruptions, those leading to high impact space weather disturbances at the near-Earth environment. Here, we report regular solar mapping made at X-band (8.1 -- 9.2 GHz) with the Arecibo 12-m radio telescope. This has demonstrated its potential for identifying active regions, about one half to a day in advance, when they rotate on to the central meridian of the Sun, and predicting the strongest flares and coronal mass ejections directed towards the Earth. Results show (i) a good correlation between the temporal evolution of brightness temperature of active regions and their magnetic configurations; (ii) the ability of the mapping data to provide a better picture of the formation sites of active regions and to accurately track their evolution across the solar disk, giving forewarning of intense solar eruptions leading to severe space weather consequences; (iii) the importance of long-term monitoring of the Sun at X-band for understanding the complex three-dimensional evolution of solar features as a function of solar activity. The key point in this study is the identification of the magnetic properties of active regions on the solar disk to aid in improving forecast strategies for extreme space-weather events.