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The AIRIX induction accelerator used for flash X-ray radiography is operational for two years, at CEA-Moronvilliers near REIMS (France). This single shot machine is composed by: (1) an injector that delivers a 3.6 - 4 MeV/2-3 kA/60 ns electron beam. (2) an accelerator composed by 16 blocks of 4 induction cells, that accelerate and transport the electron beam until 20 MeV. (3) 32 High Voltage generators that powered the induction cells: 250 kV per cell. (4) a drift and focalizing section, that transport the beam from the accelerator to the final Tantalum target. The acceptance test of this installation has been made in 2000. For that step we have choosen to work with a 2 kA electron beam. All the criteria for AIRIX qualification for hydrotest experiment have been reached with this current. We present in this paper the different measurements we made to characterize the electron beam from the injector until the end of the accelerator and the adequation with the results and the beam transport calculation. The beam image is realized with a fast gated camera that observes the Optical Transition Radiation(OTR) (produced when a charged particle passes from the vacuum to the material of a metallic foil) or Cerenkov Radiation (CR). To insure the AIRIX peformances in the time and to improve them, we have begun some specific studies. In parallel to simulation codes for beam transport, we develop optical diagnostics. The idea is to explore the intrinsic characteristics of OTR to measure the electron beam profile and electron beam divergence in a single and same shot. That will also permit the measurement of the emittance of the beam. Those measurement will able to be time resolved if we associate a streak camera. For specific hydrotest experiment we will need to have more useful X-ray dose. To increase this parameter, we have begun some studies with a 3 kA electron beam. We show in this paper the electron beam characterization made at this current and the comparison with calculations. The other part that was included in the AIRIX project concerns the X-ray imaging. For that, we have developed a system, called the gamma camera, baed on segmented scintillator associated to an MCP amplificator and a film readout. We present in this paper a first improvement of the film readout of this system.
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