Abstract
In the study of the asymmetry of the coronal lines, it is important to locate the line center as accurately as possible. This paper investigates the secondary component impact on the main profile center position and the effect of the wrong center position on the amount of asymmetry. It is shown that the secondary profile can shift the main profile center by the amount of δv <1 km/s and that the profile center position error of 5 km/s can change the asymmetry assessment by several times. A method for the determination of the observed asymmetric profile center is proposed. It consists in the fact of writing Doppler expressions for the four points of the red wing by taking the main profile as Gaussian and in computing the line center based on then these expressions.
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Original Russian Text © S.G. Mamedov, D.M. Kuli-Zade, R.F. Ismailli, 2015, published in Kinematika i Fizika Nebesnykh Tel, 2015, Vol. 31, No. 5, pp. 49–60.
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Mamedov, S.G., Kuli-Zadeb, D.M. & Ismaillia, R.F. Some problems of asymmetry of coronal spectral lines. Kinemat. Phys. Celest. Bodies 31, 245–252 (2015). https://doi.org/10.3103/S0884591315050062
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DOI: https://doi.org/10.3103/S0884591315050062