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Observation of Plasma Focusing of a 28.5 GeV Positron Beam

78   0   0.0 ( 0 )
 نشر من قبل Clive Field
 تاريخ النشر 2001
  مجال البحث فيزياء
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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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