CERN Accelerating science

Article
Report number	arXiv:1111.4354 ; CERN-2011-007 ; PP.-15-65
Title	Theory of electromagnetic fields
Author(s)	Wolski, Andrzej (Liverpool U. ; Cockcroft Inst. Accel. Sci. Tech.)
Publication	CERN, 2011
Imprint	21 Nov 2011
Number of pages	51
Note	Comments: Presented at the CERN Accelerator School CAS 2010: RF for accelerators, Ebeltoft, 8-17 June 2010 Presented at the CERN Accelerator School CAS 2010: RF for accelerators, Ebeltoft, 8-17 June 2010
In:	CAS - CERN Accelerator School: RF for Accelerators, pp.15-65
DOI	10.5170/CERN-2011-007.15
Subject category	Accelerators and Storage Rings
Abstract	We discuss the theory of electromagnetic fields, with an emphasis on aspects relevant to radiofrequency systems in particle accelerators. We begin by reviewing Maxwell's equations and their physical significance. We show that in free space, there are solutions to Maxwell's equations representing the propagation of electromagnetic fields as waves. We introduce electromagnetic potentials, and show how they can be used to simplify the calculation of the fields in the presence of sources. We derive Poynting's theorem, which leads to expressions for the energy density and energy flux in an electromagnetic field. We discuss the properties of electromagnetic waves in cavities, waveguides and transmission lines.
Copyright/License	publication: © 2011-2025 CERN (License: CC-BY-3.0)

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