Undulator

An undulator is an insertion device from high-energy physics and usually part of a larger installation, a synchrotron storage ring, or it may be a component of a free electron laser. It consists of a periodic structure of dipole magnets. The static magnetic field is alternating along the length of the undulator with a wavelength ${\displaystyle \lambda _{u}}$. Electrons traversing the periodic magnet structure are forced to undergo oscillations and thus to radiate energy. The radiation produced in an undulator is very intense and concentrated in narrow energy bands in the spectrum. It is also collimated on the orbit plane of the electrons. This radiation is guided through beamlines for experiments in various scientific areas.

The undulator strength parameter

${\displaystyle K={\frac {eB\lambda _{u}}{2\pi m_{e}c}}}$

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