New beam delivery system design for industrial electron accelerator at Nuclear Science and Technology Research Institute, Iran.

The output beams generated by industrial electron accelerators should be swept over the product. It is necessary to determine the exact scan length in order to ensure that an efficient dose reaches the product and to avoid the loss of the beam in contact with the sides of the product. Another challenge associated with scanning beams is the non-uniformity of the dose across the entire product during irradiation. In this study, the use of beam correction magnets is proposed for correcting products that receive a non-uniform dose. These magnets correct beams that are not swept in parallel. In addition, we simulated the dose received by the products in two non-uniform and uniform modes (modified by beam correction magnets) using the Monte Carlo method, and compared the results to assess the importance of using an appropriate irradiation system. Among the proposed magnets, a modified sector magnet is recommended for correcting the beam path and reducing the side effect. Using this magnet for a long horn does not require a cooling system, but using it for a short horn increases the need for a water-cooling system.

Experimental determination of some equilibrium parameter of Damavand tokamak by magnetic probe measurements for representing a physical model for plasma vertical movement.

This investigation is about plasma modeling for the control of vertical instabilities in Damavand tokamak. This model is based on online magnetic measurement. The algebraic equation defining the vertical position in this model is based on instantaneous force-balance. Two parameters in this equation, including decay index, n, and lambda, Λ, have been considered as functions of time-varying poloidal field coil currents and plasma current. Then these functions have been used in a code generated for modeling the open loop response of plasma. The main restriction of the suitability analysis of the model is that the experiments always have to be performed in the presence of a control loop for stabilizing vertical position. As a result, open loop response of the system has been identified from closed loop experimental data by nonlinear neural network identification method. The results of comparison of physical model with identified open loop response from closed loop experiments show root mean square error percentage less than 10%. The results are satisfying that the physical model is useful as a Damavand tokamak vertical movement simulator.