This book arises from the significant quantity of original results in
the field of impact spectropolarimetry, mainly for solar flare studies,
and the evident potential applications of this technique to
environmental physics, astrophysics, and hot plasma. This is a
practically oriented book, describing theoretical fundamentals and
implementation of this new interdisciplinary remote sensing technique. A
basic phenomenon for impact spectropolarimetric sensing is the
polarization ofthe electron shells of an ensemble of free atomic
particles (atoms, ions, molecules) due to collisional interaction. Slow
collisions in the presence of internal anisotropies in the relative
velocity space inside any ionized medium, as well as bombardment of a
diluted gas by fast precipitating light projectiles, are analyzed in
detail as principal impact polarization mechanisms. Impact spectro-
polarimetric sensing incorporates state-of-the-art theoretical methods
of colli- sional physics in combination with reliable polarimetric
measurements. This technique is illustrated by the new quantitative
sensing of energy transport to the upper region of the chromosphere
during solar flares, making use of ground- based solar
spectropolarimetric observations. Apart from general astrophysical and
solar-terrestrial significance, a solar flare, the brightest nonthermal
phenomenon, is a good candidate for the demonstration of new
opportunities of impact spectropolarimetry. New astrophysical
achievements of quantitative spectropolarimetry are particularly
considered in this book. The theoretical part presents a quantum
mechanical description of impact polarization and the
spectropolarimetric manifestations for different energies of the
colliding partners.
