Faraday Cups (FCs) have been used since a long time to measure the beam current in particle accelerators. The charge collected by the beam stopper is used to measure the intensity of the beam current by an ammeter. Here, at IPR (Institute for Plasma Research) the Faraday cup is used to measure the deuteron beam current in 14 MeV neutron generator. The FC presently used is for 300 KeV beam and 500μA beam current whereas the new design is proposed for deuteron beam ranging from 300–400 KeV and 20mA beam current. The energy of Ion beam is usually very high in comparison to the work function of the material resulting in the emission of the secondary electrons which can escape from the cup and effect the current measurement. Simulations for the suppressor voltage required to suppress all the secondary electrons has been carried out using SIMION8.0 and LORENTZ. Materials like Copper, Molybdenum, Tantalum etc are commonly used in manufacturing of FCs and the present paper shows the inter-comparison between the use two FC material namely Copper and Molybdenum. The heat load deposited from the beam has been analytically simulated and proper cooling system has been suggested. Simulations for selection of FC material and heat load are needed to be carried out for the new FC and its cooling system, using analysis tools like SRIM, ANSYS WORKBENCH etc. The results of these analysis are reported in this paper. The final fabrication of the FC will be based on these simulations and analysis.

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The radial profiles of ion current density are measured using a combination of two techniques—fixed parallel wires and a Faraday cup array—in a ring cusp ion source. These measurements are carried out for Ar+ ion beam current in the range of 20–90 mA and energy in the range of 850–1650 eV. Current density profiles near the extraction plane of the ion source are obtained by Abel inversion of the profiles of current measured using the parallel wires. In addition, the Faraday cup array provides radial profiles of ion current density at two different locations along the beam axis. A numerical model is developed and utilized for estimating the beam divergence and focal length from the profiles of ion current density measured using the two techniques. A fixed parallel wire array is established as an effective method for monitoring the ion beam profiles close to the ion source's extraction plane when the ion beam is utilized for other applications. The performance of the two measurement techniques is compared by estimating the ion beam current from the measurement of ion current density with the beam current measured from the power supply.