Electron bunches

The stroboscopic pulse radiolysis with the single bunch electron pulse instead of pulse trains started in Argonne National Laboratory in 1975 [54]. The research fields have been extended by the stroboscopic pulse radiolysis with the picosecond single electron bunch, although most of researches had been limited to hydrated and solvated electrons in the aqueous and alcoholic solutions. This system was unable to study the kinetics of the geminate ion recombination in liquid hydrocarbons until the modification of the Argonne linac in 1983, which made possible the quality measurements of the weak absorption. 

Gyrotrons are powerful vacuum tubes that emit pulsed or CW millimeter-wave beams (20 to 250 GHz, kW to 2 MW) by bunching electrons with cyclotron motion in a strong magnetic field. 

The effect of electron bunching or propagation of electron charge waves in the electron beam is observed in a form of an electron beam current. If the cross-sectional area of the electron beam is S, (in square meter), then the electron beam current that contains bunched electrons is... 

The catcher of a two-cavity klystron amplifier can be replaced by the slow-wave structure of a traveling wave tube, as shown in Fig. 6.24(b). This type of tube is termed the twystron (Ishii, 1989). The slow-wave structure provides a broader frequency bandwidth than a regular two-cavity klystron. A microwave input fed into the buncher cavity produces velocity modulation to the electron beam. The electron beam is bunched while drifting, and the bunched electrons induce a microwave voltage in the microwave slow-wave structure. The electron beam is focused by the use of longitudinally applied magnetic flux density B. 

Catcher A cavity resonator of a multicavity klystron proximite to the collector to catch microwave energy from the bunched electrons. 

Mi etron A microwave vacuum tube oscillator in which microwaves in a number of cavity resonators interact with bunched electrons in motion rotating or rectihnearly. The basic electron motion is formed by the appUed accelerating electric fields and the DC magnetic fields. 

---