Estimation of solar prominence magnetic fields based on the reconstructed 3D trajectories of prominence knots

TL;DR

This study estimates the lower limits of magnetic fields in solar prominences by reconstructing 3D trajectories of prominence knots using ground-based observations, providing insights into magnetic field strengths in different prominence types.

Contribution

The paper introduces a method to estimate magnetic field lower limits in prominences based on 3D trajectory reconstruction from spectroscopic data, under the equipartition assumption.

Findings

Magnetic fields in surges range from 16 to 40 Gauss.

In quiescent and activated prominences, magnetic fields are less than 10 Gauss.

Results align with previous detections of weak magnetic fields in prominences.

Abstract

We present an estimation of the lower limits of local magnetic fields in quiescent, activated, and active (surges) promineces, based on reconstructed 3-dimensional (3D) trajectories of individual prominence knots. The 3D trajectories, velocities, tangential and centripetal accelerations of the knots were reconstructed using observational data collected with a single ground-based telescope equipped with a Multi-channel Subtractive Double Pass imaging spectrograph. Lower limits of magnetic fields channeling observed plasma flows were estimated under assumption of the equipartition principle. Assuming approximate electron densities of the plasma n_e = 5*10^{11} cm^{-3} in surges and n_e = 5*10^{10} cm^{-3} in quiescent/activated prominences, we found that the magnetic fields channeling two observed surges range from 16 to 40 Gauss, while in quiescent and activated prominences they were less than 10 Gauss. Our results are consistent with previous detections of weak local magnetic fields in the solar prominences.