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Die Kreisbogenartige Spur eines Positrons in einer Nebelkammer: die Länge und die Krümmung der Spur geben Rückschlüsse auf das Teilchen selbst. Die Krümmung kommt durch ein von außen angelegtes Magnetfeld zustande. Infolge der magnetischen Komponente der Lorentzkraft wird eine bewegte Ladung dort von ihrer Bahn abgelenkt.

Original caption: A 63 million volt positron (Hρ = 2.1×105 gauss-cm) passing through a 6 mm lead plate and emerging as a 23 million volt positron (Hρ = 7.5×104 gauss-cm). The length of this latter path is at least ten times greater than the possible length of a proton path of this curvature.

Original publication: Anderson, Carl D. (1933). "The Positive Electron". Physical Review 43 (6): 491–494. DOI:10.1103/PhysRev.43.491

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