[en] We proposed and analyzed a new, simple and easily realized electrostatic undulator. The electrostatic undulator free electron laser theory as well as the selffocusing mechanism of the undulator were presented

[en] In this paper, transport experiment of beam (500 keV, 1.2 kA) is discribed. A annuler beam is generated by EPA-74 pulseline accelerator. The beam propagates through a drift tube with 5.2 cm i.d. and the length of 80 cm, which is immersed in axial magnetic field. The beam has a 4 cm diameter and thickness of 0.1 cm at 70 cm from cathode. Properties of the beam and relation of beam with guide field are discussed. (author)

[en] An elctron beam, generated by the concave focusing cathode of EAP-74 pulseline accelerator, is injected into the bifilar helical wiggler with a matching thin solenoidal lens. The wiggler length L_W = 1.5 m, with period λ_W = 3.45 cm. 130A electron beam are obtained at the end of the wiggler exit under the wiggler magnitude of 1.25 kG. The growth rate of 130 dB/m is obtained by measuring the output power as a function of the wiggler interaction length. Saturation phenomenon and saturation power of 7.6 MW are observed and measured also at L_W ≥ 0.9 m, and an efficiency of 5% has been achieved. Spectral diagnosing of 35-38 GHz is performed with a waveguide dispersive line. The tolal output energy of 41-48 mJ is measured with the calorimeter. The waveguide mode in the interaction region is TE₁₁ Mode

[en] Short communications only

[en] The high-bright X-ray can be generated by the back-Compton scattering through the laser with electron beam, and the wavelength is tunable by changing the electron energy. Because of the low scattering chance of the scattering photon with the electro, it is difficult to acquire the high-bright radiation. The high power density laser and the high-bright electron beam is required to obtain the high-bright radiation. In the experiment, the electron beam of CAEP RF photo-injector together with 30 MeV linac and the high power density laser in Nd:YAG laser cavity will be used, the radiation wavelength is 0.07-0.14 nm, the radiation ability expected to be about 2.5 x 10¹¹ photons per second, and the radiation wavelength can be tuned by changing the electron energy

[en] The photo-injected energy recovery LINAC (PERL) is a product of two basic techniques: the photo-injector and the superconducting energy recovery linac. Its major performances is to get the high brightness and high average power electron beams, operating for CW, and there are good application vistas in the high radiation field, include high average power FEL and new generation light sources. The photo-injector is the best source for the production of high-brightness electron beams. The superconducting energy recovery linac can deliver non-stored intense-current electron beams. This paper presents a preliminary study on the DC gun photo-injector and the superconducting cavity linac. When the DC high voltage is greater than or equal to 1 MV and the accelerating field is greater than or equal to 10 MV/m, the photo-injector output electron beams can meet the PERL application needs

[en] The authors introduce the frequency and power measurements of SG-1 Free Electron Laser (FEL) amplifier, which generates 140 MW power, and analyze the influence of X-ray on the measurement and responses of microwave devices to short pulses

[en] Electron backbom and the beam qualities of the RF-gun in the real conditions is investigated by means of particles simulations. The influences of the cavity length and amplitude of electric field are presented. And the methods decreasing the power of backbom are discussed

[en] The entrance magnetic field and self-focusing of the linearly polarized wiggler produced by double bifilar helix lines is investigated. (1) The integral formula of the magnetic field on Z axis of the wiggler is derived, the prediction by the formula is good with the experiment, the results show that the field symmetry is better than the bifilar helix wiggler's. (2) According to Lorentz equation, authors have derived the electro trajectory equations with the stable motions, and the formula about the threshold transport e-beam current and the wiggler peak field, simulated the orbits of the electron at edge in the wiggler, those give authors a result that the wiggler has a ability of self-focusing, and can be applied in the linearly polarized FEL experiment

[en] Beams emittance is a very important parameter of the RF-injector, it is growth due to RF field space charge effects and so on. The analytical expression of beams emittance in RF injector has been given in this paper, it shows that beams emittance is various in RF injector. The dependences of beams emittance at the exit of a 1 + 1/2 cell photo-cathode injector on field strength, initial phase, beam size, bunch length and charge, etc are researched respectively using SUPERFISH and GPT programs. Beams emittance of less than 2πmm·mrad can be obtained by appropriately choosing these parameters