English

Measuring the Coronal Magnetic Field with 2D Coronal Seismology: A Forward-Modeling Validation

Solar and Stellar Astrophysics 2026-01-16 v1

Abstract

In recent years, a two-dimensional (2D) coronal seismology technique applied to spectral-imaging data from the Coronal Multi-channel Polarimeter (CoMP) and UCoMP has enabled routine measurement of the global coronal magnetic field. The technique combines coronal transverse wave phase speed from Doppler measurements with electron densities from the Fe \sc{xiii}\rm{} 10798/10747 \AA\ intensity ratio to infer the magnetic field strength, while the wave propagation directions from Doppler measurements trace the magnetic field direction. To validate the accuracy and robustness of this method, we use forward modeling of a MURaM simulation that produces open and closed magnetic structures with excited waves. From the synthetic Doppler velocity, Fe \sc{xiii}\rm{} infrared line intensities, and linear polarization signals, we apply the 2D coronal seismology technique to estimate the magnetic field strength and direction. A comparison with the simulation ground truth shows close agreement, indicating that the technique can recover the line-of-sight emissivity-weighted magnetic field direction and strength with high accuracy. We also perform a parameter-space analysis to quantify sensitivities of the method to parameter choice. These findings provide practical guidance for CoMP/UCoMP-like analysis and demonstrate that 2D coronal seismology can deliver reliable, LOS emissivity-weighted measurements of the coronal magnetic field from coronal wave observations.

Keywords

Cite

@article{arxiv.2601.10637,
  title  = {Measuring the Coronal Magnetic Field with 2D Coronal Seismology: A Forward-Modeling Validation},
  author = {Zihao Yang and Sarah Gibson and Matthias Rempel and Giuliana de Toma},
  journal= {arXiv preprint arXiv:2601.10637},
  year   = {2026}
}

Comments

17 pages, 10 figures, accepted for publication in ApJS

R2 v1 2026-07-01T09:06:22.307Z