Paper presented at AGU Fall Meeting, 8-12 December 1997, San Fransico, CA, USA
Using the first year of data from the CELIAS/MTOF sensor on board of SOHO spacecraft we have investigated isotopic fractionation processes in the solar wind. The refractory elements like Magnesium can not be modified anywhere within the Sun by convential hydrogen burning. Therefore, this element consitutes a "standard" to derive constraints on fractionation effects of solar wind particles on their way from the source region in the photosphere to the interplanetary medium. We have analyzed the data for Magnesium isotopes measured at different solar wind conditions. We have compared our results with meteoritic isotope abundances and solar wind data from other spacecraft missions and we have found very good agreement. Furthermore, we have studied the dependence of Magnesium isotope abundances on different solar wind parameters.