Elemental fractionation in the slow solar wind

Slow solar wind, found at low heliographic latitudes, and fast solar wind, associated with high-latitude coronal holes, are fundamentally different: s low solar wind is more variable and is biased in elements with low first io nization potentials (FIPs), whereas fast solar wind is steady and has at mo st limited FIP bias. It has been recently argued that these differences are consequences of a continuous reorganization of the Sun's magnetic held des cribed by a new heliospheric magnetic field model. This continuous reorgani zation requires a sustained reconnection process at low latitudes between o pen magnetic held lines and large coronal loops. Arguably, the slow solar w ind originates from material stored on large coronal loops which is release d sporadically because of reconnection. The fast solar wind is released on continuously open magnetic field lines. In this paper a theory for FIP frac tionation is developed which depends on the wave heating of minor ions whic h extends below the transition region. The wave heating may be natural on t he closed held configurations of large coronal loops but not in the open co nfigurations associated with fields emanating from coronal holes. Therefore , the theory naturally leads to a differentiation in FIP fractionation betw een fast and slow solar wind.