Magnetic Field Extrapolations into the Corona: Success and Future Improvements

摘要: The solar atmosphere being magnetic in nature, the understanding of structure and evolution field different regions has been an important task over past decades. This made complicated by difficulties to measure corona, while it is currently known with a good accuracy photosphere and/or chromosphere. Thus, determine coronal field, mathematical method developed based on observed field. so-called extrapolation technique. technique relies two crucial points: i) physical assumption leading system differential equations be solved, ii) choice quality associated boundary conditions. In this review, I summarise assumptions use findings at scales atmosphere. concentrate discussion techniques applied data comparison observations broad range wavelengths (from hard X-rays radio emission).