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arXiv · 1912.03340

Using the Stokes V widths of Fe I lines for diagnostics of the intrinsic solar photospheric magnetic field

M. Gordovskyy·S. Shelyag·P. K. Browning·V. G. Lozitsky
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Abstract

The goal of this study is to explore a novel method for the solar photospheric magnetic field diagnostics using Stokes V widths of different magnetosensitive Fe~I spectral lines. We calculate Stokes I and V profiles of several Fe I lines based on a one-dimensional photospheric model VAL C using the NICOLE radiative transfer code. These profiles are used to produce calibration curves linking the intrinsic magnetic field values with the widths of blue peaks of Stokes V profiles. The obtained calibration curves are then tested using the Stokes profiles calculated for more realistic photospheric models based on MHD models of magneto-convection. It is shown that the developed Stokes V widths (SVW) method can be used with various optical and near-infrared lines. Out of six lines considered in this study, FeI 6301 line appears to be the most effective: it is sensitive to fields over ~200G and does not show any saturation up to ~2kG. Other lines considered can also be used for the photospheric field diagnostics with this method, however, only in narrower field value ranges, typically from about 100G to 700-1000G. The developed method can be a useful alternative to the classical magnetic line ratio method, particularly when the choice of lines is limited.

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M. Gordovskyy, S. Shelyag, P. K. Browning, V. G. Lozitsky. 2019-12-06. Using the Stokes V widths of Fe I lines for diagnostics of the intrinsic solar photospheric magnetic field. https://doi.org/10.1051/0004-6361/201937027

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