| The thesis described the need for the measurement of the length of pico-second electron bunch. Several typical measurement methods for it have been given and discussed here. A novel way by means of time-energy conversion process was proposed, and the meaning for developing it was discussed.For measurement of the length of the electron bunch produced by the existing micro-pulse gun (MPG) device in NSRL, the design and construction work for the measurement system has been done. The electron bunch form the MPG in NSRL has the following parameters: the kinetic energy is about 300keV, low energy dispersion (about 0.1%), the peak current is about 10A～100A, the length of electron bunch is in pico-second. With the help of "Parmela", the strong space charge force would distort the original electron bunch. To such electron bunch its length could not be got by time-energy conversion measurement. In order to overcome it, an accelerating structure (so called "accelerating section") was connected with the MPG to offer the electrons extra energy to weaken the space-charge-effect. Another accelerating structure (so called "time-energy conversion section") was used to convert the electron bunch to energy just behind the first one.For such an electron bunch from MPG defined before, an entire measurement system has been discussed, including accelerating process, time-energy conversion process, energy analysis, and so on. With the knowledge of beam dynamics theory, the code has been edited to get the original parameters of disk-loaded structure, focus system and energy analysis system. And then we simulated the motion of the electron bunch in the measurement system with the original parameters so as to correct the original parameters by "Parmela".We defined the physics property of dipole, and got the original structural parameters by theory formula. The three-dimension simulation of dipole to find the final structural parameters was finished by Mafia and Opera respectively. We...
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