Robust method for determination of magnetic field strength in solar photosphere
Heading:
| 1Prysiazhnyi, AI, 1Stodilka, MI, 2Shchukina, NG 1Astronomical Observatory of Ivan Franko National University of Lviv, Lviv, Ukraine 2Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine |
| Kinemat. fiz. nebesnyh tel (Online) 2018, 34(6):3-21 |
| https://doi.org/10.15407/kfnt2018.06.003 |
| Start Page: Solar Physics |
| Language: Ukrainian |
Abstract: We modify the classical method for determining the magnetic field strength from the distance between the peaks of blue and red wings of the Stokes V profile of magnetically sensitive spectral line. To reduce the influence of noise and to measure more accurately the distance between these peaks the observed Stokes V profile was approximated by a modified wavelet-function. The parameters of the best fitted approximation function were determined by multidimensional optimization. Following such an approach, the magnetic field strength can be found analytically using these parameters. We investigate the modified method by means of calculations of the Fe I λ 1564.8 nm Stokes V and I profiles in a three-dimensional snapshot model atmosphere. We used a magneto-convection simutations with small-scale dynamo action performed by Rempel. We find that the method proposed is less sensitive to noise and shape of the observed V-signal of the line. This makes it possible to conclude that our approach of determing of the magnetic field strength from the observed splitting of the Fe I X 1564.8 nm Stokes V profile is more reliable in comparison with the classical one. |
| Keywords: diagnostic, magnetic fields, photosphere, Sun, Zeeman effect |
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