Magnetic Fields through Polarimetry: Progress on Grain Alignment Theory
Alex Lazarian
University of Wisconsin
Résumé :
ISM is magnetized with magnetic field influencing almost all of
its properties. One of the most informative techniques to study magnetic
is based on the use of starlight polarization and polarized emission
arising from aligned dust. Grain alignment theory addresses the
issue of how reliable the interpretation of the polarization maps in
terms of magnetic fields is. Although grain alignment is a problem
of half a century standing, recent progress achieved in the field makes me
believe that we are close to solving this mistery. I review basic
physical processes involved in grain alignment and discuss
the niches for different alignment mechanisms. I show that the some
of textbook mechanims are not so promissing, while the radiative
torque mechanism ignored for more than 20 years after its introduction
looks most attractive.
