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Observation of Plasma Focusing of a 28.5 GeV Positron Beam

J. S. T. Ng·P. Chen·H. Baldis·P. Bolton·D. Cline·W. Craddock·C. Crawford·F. J. Decker·C. Field·Y. Fukui·V. Kumar·R. Iverson·F. King·R. E. Kirby·K. Nakajima·R. Noble·A. Ogata·P. Raimondi·D. Walz·A. W. Weidemann
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Abstract

The observation of plasma focusing of a 28.5 GeV positron beam is reported. The plasma was formed by ionizing a nitrogen jet only 3 mm thick. Simultaneous focusing in both transverse dimensions was observed with effective focusing strengths of order Tesla per micron. The minimum area of the beam spot was reduced by a factor of 2.0 +/- 0.3 by the plasma. The longitudinal beam envelope was measured and compared with numerical calculations.

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J. S. T. Ng, P. Chen, H. Baldis, P. Bolton, D. Cline, W. Craddock, C. Crawford, F. J. Decker, C. Field, Y. Fukui, V. Kumar, R. Iverson, F. King, R. E. Kirby, K. Nakajima, R. Noble, A. Ogata, P. Raimondi, D. Walz, A. W. Weidemann. 2001-10-04. Observation of Plasma Focusing of a 28.5 GeV Positron Beam. https://doi.org/10.1103/physrevlett.87.244801

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