First observations of intensity-dependent effects for transversally split beams

During the commissioning of the CERN PS Multi-Turn Extraction (MTE) tests with different beam intensities were performed. The initial beam current before transverse splitting was varied and the properties of the five beamlets obtained by crossing the fourth-order horizontal resonance were studied. A clear dependence of the beamlets’ parameters on the total intensity was found, which is the first direct observation of intensity-dependent effects for such a peculiar beam type. The experimental results are presented and discussed in this paper.