The Zeeman Effect in the Interstellar Medium
The Zeeman Effect in the Interstellar Medium
This Demonstration discusses the effects of a magnetic field on observations of certain emission lines. Strong magnetic fields can split emission and absorption lines, an effect discovered by Pieter Zeeman in 1896. This is one of the very few ways scientists can measure magnetic field strength in the interstellar medium. By matching the observed Stokes V profile with a scaled derivative of the Stokes I (details below), the line-of-sight strength of the magnetic field can be determined.