Electron Gun


The thermionic electron source is designed for the radiation source ELBE* (Electron Linac for beams with high Brilliance and low Emittance) project- HZDR (Helmholtz-Zentrum Dresden-Rossendorf) at Dresden and still in operation. The mechanical design of gun is obtained from HZDR with collaboration. A standard cathode is used to generate electrons in this gun (Eimac Y-845). There are three options to create electron beam from thermionic electron source (triode), one is DC electron beam, another one is electron bunched beam and the other one is macro pulsed beam. Electron bunches will be created at required frequencies by grid system, which is located very close to cathode. Basically the bunch repetition frequency will be 13 MHz and running frequency of the accelerator will be 1.3 GHz. Electron source consists of a two-stage electrostatic acceleration section to accelerate the electron beam up to maximum 300 keV. In real operation electron beam energy will be 250keV and average electron beam current will be around 1mA identical to 77pC. Also The TARLA** (Turkish Accelerator and Radiation Laboratory in Ankara) has capability to provide up to 120 pC bunch charge with higher emittance and beam current around 1.6mA.However achievable shortest bunch length at the exit of gun will be about 500ps. Picture-1a and 1b shows that test set up of TARLA thermionic electron source.

                                                                   Picture-1a Transfer Line


                                                                Picture-1b HV Platform


For detail information please look at the technical design report of TARLA (second version).


References :

*Radiation Source ELBE – www.hzdr.de

** The technical design report of TARLA (2. version)

Contact Person : Çağlar Kaya (c.kaya@ankara.edu.tr)