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Nonlinearities and Effects of Transverse Beam Size in Beam Position Monitors (revised)

Sergey S. Kurennoy
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Abstract

The fields produced by a long beam with a given transverse charge distribution in a homogeneous vacuum chamber are studied. Signals induced by a displaced finite-size beam on electrodes of a beam position monitor (BPM) are calculated and compared to those produced by a pencil beam. The non-linearities and corrections to BPM signals due to a finite transverse beam size are calculated for an arbitrary chamber cross section. Simple analytical expressions are given for a few particular transverse distributions of the beam current in a circular or rectangular chamber. Of particular interest is a general proof that in an arbitrary homogeneous chamber the beam-size corrections vanish for any axisymmetric beam current distribution.

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Sergey S. Kurennoy. 2003-02-11. Nonlinearities and Effects of Transverse Beam Size in Beam Position Monitors (revised). https://doi.org/10.1103/physrevstab.4.092801

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