Testing algorithm for the computation of the transverse emittance of the ion beams generated by the ECR mVINIS ion source based on a pepper-pot method

Abstract Without knowing the emittance value, it is difficult to optimize ion beam optics for minimum beam loss during transmission, especially considering the very high emittance values of electron cyclotron resonance (ECR) ion sources. With this in mind, to measure the emittance of the ion beams produced by the mVINIS ECR, which is part of the FAMA facility at the Vinča Institute of Nuclear Sciences, we have developed a pepper-pot scintillator screen system combined with a CMOS camera. The application, developed on the LabVIEW platform, allows us to control the camera’s main attribute settings, such as the shutter speed and the gain, record the images in the region of interest, and process and filter the images in real time. To analyze the data from the obtained image, we have developed an algorithm called measurement and analysis of ion beam luminosity (MAIBL) to reconstruct the four-dimensional (4D) beam profile and calculate the root mean square (RMS) emittance. Before measuring emittance, we performed a simulated experiment using the pepper-pot simulation (PPS) program. An exported file (PPS) gives a numerically generated raw image (mock image) of a beam with a predefined emittance value after it has passed through a pepper-pot mask. By analyzing data from mock images instead of the image obtained by the camera and putting it into the MAIBL algorithm, we can compare the calculated emittance with PPS’s initial emittance value. In this paper, we present our computational tools and explain the method for verifying the correctness of the calculated emittance values.