Electron spectrometer
From Wikipedia, the free encyclopedia
An electron spectrometer is a device used to perform different forms of electron spectroscopy and electron microscopy. This requires analyzing the energy of an incoming beam of electrons. Most electron spectrometers use a hemispherical electron energy analyzer in which the beam of electrons is bent with electric or magnetic fields. Higher energy electrons will be bent less by the beam, this produces a spatially distributed range of energies.
Electron spectrometers are used on a range of scientific equipment, including particle accelerators, transmission electron microscopes, and astronomical satellites.
Electron spectrometers may determine electron energy based on time of flight, retarding potential (effectively a high-pass filter), resonant collision or curvature in a deflecting field (magnetic or electric).[1]
An electrostatic electron spectrometer uses the electric field, which cause electrons to move along field gradients, whereas magnetic devices cause electrons to move at right angles to the field. Magnetic fields will act in a direction perpendicular to the electron propagation, thereby conserving velocity, whereas electrostatic fields will cause electrons to move along the field gradient,[2] which may change electron energies if the component of the direction of propagation and field gradients are not perpendicular. Owing to these effects, sector based designs are commonly used in electron spectrometers.
