Machine Protection

Lars Fröhlich


Conventional linacs used for modern free-electron lasers carry electron beams of unprecedented brightness with average powers ranging from a few watts to hundreds of kilowatts. Energy recovery linacs are already operated as radiation sources with nominal electron beam powers beyond 1 MW, and this figure can only be expected to increase in the future. This lecture discusses the scope of machine protection for these accelerators, reviews the parameters of existing and planned facilities, and gives an overview of typical hazards and damage scenarios. A brief introduction to the interaction of electron beams with matter is given, including a simple model for estimating some properties of electromagnetic cascades. A special problem common to most light sources—the field loss of permanent magnet undulators and its consequences for the emission of radiation—is discussed in the final section.


Machine protection; linear accelerators; free-electron lasers; energy recovery linacs; radiation-induced demagnetization.

Full Text:




  • There are currently no refbacks.