|Abstract : ||The Solar Mean Magnetic Field (SMMF) is the mean value of the Line-of-Sight (LOS) component of the solar magnetic field averaged over the visible hemisphere of the Sun. So far, studies of the SMMF have been confined to the magnetic field measurements at the photosphere. In this study, we calculate and study the SMMF using magnetic field measurements at the chromosphere, in conjunction with that of photospheric measurements.
For this purpose, we have used full disk LOS magnetograms derived from the spectropolarimetric observations carried out in Fe I line at 630.15 nm (photosphere) and Ca II line at 854.2 nm (chromosphere) by the SOLIS/Vector Spectromagnetograph (VSM) instrument during 2010 – 2017. It is found from this study that the SMMF at the chromosphere is weaker by a factor of 0.84 compared to the SMMF at the photosphere. The correlation analysis between them gives a Pearson correlation coefficient of 0.81. The existence of the chromospheric SMMF and its similarity to the photospheric SMMF corroborate the idea that the SMMF is the source of the Interplanetary Magnetic Field (IMF).|