Beam Charge Measurements

The measurement of beam charge is fundamental to all particle accelerators. There exist many methods to achieve this, which can broadly be classified into two categories: intercepting measurements, which are destructive for the beam and result in absorption of a significant amount of energy and non-intercepting measurements using electric or magnetic field coupling. In both categories one can find instruments that process the beam signals with high dynamic range, both in amplitude and time. The aim of this article is to present the current state of beam charge measurement technologies. Various measurement methods will be described with their uses, advantages, and the achievable resolution and accuracy will be discussed. The technological problems related to their fabrication will also be addressed.