Solar wind Solar wind The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma consists of mostly electrons, protons and alpha particles with kinetic energy between 0.5 and 10 keV. Embedded within the solar-wind plasma is the interplanetary magnetic field. The solar wind varies in density, temperature and speed over time and over solar latitude and longitude. Its particles can escape the Sun's gravity because of their high energy resulting from the high temperature of the corona, which in turn is a result of the coronal magnetic field. At a
Plasma diagnostics Some atoms are excited by collisions within the plasma and emit radiation. This can be used to probe density fluctuations in a turbulent plasma. In very hot plasmas (as in magnetic fusion experiments), light elements are fully ionized and don't emit line radiation. When a beam of neutral atoms is fired into the plasma, electrons from beam atoms are transferred to hot plasma ions, which form hydrogenic ions which promptly emit line radiation. This radiation is analyzed for ion density, temperature, and velocity. If the plasma is not fully ionized but contains ions that fluoresce, laser-induced fluorescence can provide very