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arXiv · 2405.16741

A Study on Magnetic-sensitivity Wavelength Position of the Working Line Used by the Full-Disk Magnetograph onboard the Advanced Space based Solar Observatory (ASO-S/FMG)

S. Liu·J. T. Su·X. Y. Bai·Y. Y. Deng·J. Chen·Y. L. Song·X. F. Wang·H. Q. Xu·X. Yang·Shahid Idrees
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Abstract

Utilizing data from the $Solar$ $Magnetism$ and $Activity$ $Telescope$ (SMAT), analytical solutions of polarized radiative transfer equations, and in-orbit test data from the Full-disk Magnetograph (FMG) onboard the Advanced Space based Solar Observatory (ASO-S), this study reveals the magnetic-sensitivity spectral positions for the Fe {\sc i} $\lambda$5234.19 A, working line used by FMG. From the experimental data of SMAT, it is found that the most sensitivity position is located at the line center for linear polarization (Stokes-Q/U), while it is about -0.07 A away from the line center for circular polarization (Stokes-V). Moreover, both the theoretical analysis and the in-orbit test data analysis of FMG prove again the above results. Additionally, the theoretical analysis suggests the presence of distinct spectral pockets (centered at 0.08-0.15 A) from the line, harboring intense magnetic sensitivity across all three Stokes parameters. Striking a balance between high sensitivity for both linear and circular polarization while capturing additional valuable information, a spectral position of -0.08 A emerges as the champion for routine FMG magnetic-field observations.

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S. Liu, J. T. Su, X. Y. Bai, Y. Y. Deng, J. Chen, Y. L. Song, X. F. Wang, H. Q. Xu, X. Yang, Shahid Idrees. 2024-05-27. A Study on Magnetic-sensitivity Wavelength Position of the Working Line Used by the Full-Disk Magnetograph onboard the Advanced Space based Solar Observatory (ASO-S/FMG). https://doi.org/10.1007/s11207-024-02311-0

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