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arXiv · 1803.06663

Direct Measurement of Focusing Fields in Active Plasma Lenses

J. -H. Röckemann·L. Schaper·S. K. Barber·N. A. Bobrova·G. Boyle·S. Bulanov·N. Delbos·K. Floettmann·G. Kube·W. Lauth·W. P. Leemans·V. Libov·A. Maier·M. Meisel·P. Messner·P. V. Sasorov·C. B. Schroeder·J. van Tilborg·S. Wesch·J. Osterhoff
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Abstract

Active plasma lenses have the potential to enable broad-ranging applications of plasma-based accelerators owing to their compact design and radially symmetric kT/m-level focusing fields, facilitating beam-quality preservation and compact beam transport. We report on the direct measurement of magnetic field gradients in active plasma lenses and demonstrate their impact on the emittance of a charged particle beam. This is made possible by the use of a well-characterized electron beam with 1.4 mm mrad normalized emittance from a conventional accelerator. Field gradients of up to 823 T/m are investigated. The observed emittance evolution is supported by numerical simulations, which suggest the potential for conservation of the core beam emittance in such a plasma lens setup.

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J. -H. Röckemann, L. Schaper, S. K. Barber, N. A. Bobrova, G. Boyle, S. Bulanov, N. Delbos, K. Floettmann, G. Kube, W. Lauth, W. P. Leemans, V. Libov, A. Maier, M. Meisel, P. Messner, P. V. Sasorov, C. B. Schroeder, J. van Tilborg, S. Wesch, J. Osterhoff. 2018-03-18. Direct Measurement of Focusing Fields in Active Plasma Lenses. https://doi.org/10.1103/physrevaccelbeams.21.122801

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