| Name: | Soham Dey |
| Affiliation: | National Centre for Radio Astrophysics |
| Conference ID: | ASI2025_632 |
| Title: | Polarization Characteristics of Active Solar Radio Emissions: Insights from SKAO Pathfinders and Precursors |
| Authors: | Soham Dey 1, Divya Oberoi 1, Devojyoti Kansabanik 2, Puja Majee 1, Pietro Zucca 3, Surajit Mondal 4, Mattia Mancinni 3 |
| Authors Affiliation: | 1 National Centre for Radio Astrophysics, Pune, India
2 University Corporation for Atmospheric Research, Boulder, Colorado, United States of America
3 ASTRON, Dwingeloo, The Netherlands
4 New Jersey Institute of Technology, Newark, United States of America
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| Mode of Presentation: | Oral |
| Abstract Category: | Sun, Solar System, Exoplanets, and Astrobiology |
| Abstract: | Solar radio bursts are among the most widely studied phenomena originating in the solar corona, and offer valuable insights into the coronal medium. Their polarization characteristics serve as tracers of coronal magnetic fields for which a direct measure has been, traditionally, very challenging . Despite their potential, the study of solar emissions at low radio frequencies has been constrained by both instrumental limitations and the lack of suitable imaging techniques. As a result, much of the existing research has focused on analyzing dynamic spectra, which, while informative, do not provide any spatial information needed to fully explore the complex behavior of these emissions.
The advent of next-generation radio telescopes, such as the Murchison Widefield Array (MWA), LOw Frequency ARray (LOFAR), and the upgraded Giant Metrewave Radio Telescope (uGMRT) — all precursors or pathfinders for the Square Kilometer Array Observatory (SKAO) — marks a significant shift in solar radio astronomy. These instruments, combined with advancements in calibration and imaging techniques, now enable high-fidelity, full-polarimetric imaging of solar radio bursts, offering new opportunities to study the dynamic emission processes with high temporal and spectral resolution in the image plane.
In this work, we present recent results from polarization imaging of active solar radio emissions using MWA, LOFAR, and uGMRT. Our findings reveal that these emissions are predominantly circularly polarized, with polarization fractions that vary significantly and remain consistently lower than the theoretical expectations. Notably, we observe that the peaks of the polarized emission sources are often separated by several arcseconds to arcminutes from that for the total intensity sources, and that the polarized emission regions are always more compact than the corresponding total intensity source. This suggests that scattering effects may play a significant role in reducing the observed polarization.
We will discuss these results and explore their implications
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