Studies of Magnetic Fields in the Solar Photosphere Using the Line-Ratio Method

摘要

The longitudinal magnetic field measured using the Fe I λ 525 and Fe Iλ 524.7 nm lines and global magnetic field of the sun differ depending on the observatory.To study the cause of these discrepancies, we calculate the H_‖(525)/H_‖(524.7) ratios for various combinations of magnetic ele-ments and compare them with the corresponding observed values. We use the standard quiet model of the solar photosphere suggesting that there are magnetic fields of different polarities in the range between zero and several kilogauss.The magnetic element distribution is found as a function of mag-netic field strength and the parameters of this distribution are determined for which the calculated H_‖(525)/H_‖(524.7) ratio agrees with the observed one.The sigma-components are found to be shifted differently for various points of the Fe I λ 525 nm profile calculated for the inhomogeneous magnetic field.The farther the point is from the line center,the larger the sigma-components shift.Such a pecu-liarity of the profiles may be responsible for the discrepancies in the measured values of the global mag-netic field obtained at different observatories. The increase in modulus of the global magnetic field during the maxima of solar activity can be due to a larger fraction of magnetic elements with kilogauss magnetic fields.