We describe a project involving the beam chopping process that develops student skills in modeling, computation, experimentation, and data acquisition and can be completed by introductory physics students.
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Beams of particles also can be chopped. Neutral particle beams can be modulated using a mechanical chopper, and charged particle beams can be chopped by electrostatic deflection (for example, deflecting a beam using an electric field so that the beam no longer passes through an aperture).
12.
The source code for the C language programs that computes for different cases, that is, and can be downloaded from 〈http://www.physics.emich.edu/molab/beamchop/index.html〉.
13.
We used a Hewlett Packard Model 54603B Oscilloscope with the Model 54650A HP-IB Interface Module together with LABVIEW software and the Model PCI-GPIB Interface Card from National Instruments to acquire the averaged oscilloscope trace shown in Fig. 6.
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Specification sheet for Part No. LTL-10233W, Lite-On Electronics, 〈www.us.liteon.com〉.
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© 2004 American Association of Physics Teachers.
2004
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