Speaker
Description
First Name: Xiang
Last Name: Li
Email Address: lixiang@mps.mpg.de
Affiliation: Max Planck Institute for Solar System Research
All Authors: Xiang Li, Gherardo Valori, Daniele Calchetti, Sami K. Solanki, Johann Hirzberger, Jonas Sinjan
Abstract: The solar vector magnetic field is inferred from spectropolarimetric observations of the polarization in magnetically sensitive spectral lines. However, the transverse component of the magnetic field has an 180° ambiguity in its orientation. Traditional single-view methods for resolving the ambiguity require assumptions on the properties of the photospheric magnetic field. Solar Orbiter (SO), and its onboard magnetograph (the Polarimetric and Helioseismic Imager, PHI), make it possible for the first time to avoid such assumptions, and to remove the ambiguity purely using observations from two vantage points. The Stereoscopic Disambiguation Method (SDM), which was developed based on this idea, has been successfully tested on simulated data and first science data from the High Resolution Telescope (SO/PHI-HRT) acquired in spring 2022. In this work, we applied the SDM to a number of SO/PHI-HRT datasets and corresponding datasets from the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO). The SDM successfully disambiguates vector magnetograms in strong field areas, and for a large range of separation angles between the viewpoints. Quantitative diagnostic metrics were studied to evaluate the reliability of the SDM in localized areas. Furthermore, we compared the disambiguation results obtained by the SDM and the single-view disambiguation method.