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arXiv · 1508.05750

Demonstration of a laserwire emittance scanner for the CERN LINAC4 H- Beam

T. Hofmann·K. O. Kruchinin·A. Bosco·S. M. Gibson·F. Roncarolo·G. Boorman·U. Raich·E. Bravin·J. K. Pozimski·A. Letchford·C. Gabor
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Abstract

A non-invasive, compact laserwire system has been developed to measure the transverse emittance of an H- beam and has been demonstrated at the new LINAC4 injector for the LHC at CERN. Light from a low power, pulsed laser source is conveyed via fibre to collide with the H- beam, a fraction of which is neutralized and then intercepted by a downstream diamond detector. Scanning the focused laser across the H- beam and measuring the distribution of the photo-neutralized particles enables the transverse emittance to be reconstructed. The vertical phase-space distribution of a 3 MeV beam during LINAC4 commissioning has been measured by the laserwire and verified with a conventional slit and grid method.

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T. Hofmann, K. O. Kruchinin, A. Bosco, S. M. Gibson, F. Roncarolo, G. Boorman, U. Raich, E. Bravin, J. K. Pozimski, A. Letchford, C. Gabor. 2015-08-24. Demonstration of a laserwire emittance scanner for the CERN LINAC4 H- Beam. https://doi.org/10.1103/physrevstab.18.122801

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