Book contents
- Frontmatter
- Contents
- Foreword
- Coordinate system
- Symbols
- Useful Constants
- 1 Introduction
- 2 Basic concepts and constant-gradient focusing
- 3 Alternating-gradient focusing
- 4 Parameterisation of the transverse motion
- 5 Imperfections and resonances
- 6 Chromaticity
- 7 Longitudinal beam dynamics
- 8 Image and space-charge forces (transverse)
- 9 Coherent instabilities
- 10 Radiating particles
- 11 Diagnosis and compensation
- 12 Special aspects of circular colliders
- Appendix A Transverse particle motion in an accelerator
- Appendix B Accelerator magnets
- Appendix C Closed orbits
- Appendix D Phase equation
- Appendix E Vlasov equation
- References
- Index
10 - Radiating particles
Published online by Cambridge University Press: 11 November 2009
- Frontmatter
- Contents
- Foreword
- Coordinate system
- Symbols
- Useful Constants
- 1 Introduction
- 2 Basic concepts and constant-gradient focusing
- 3 Alternating-gradient focusing
- 4 Parameterisation of the transverse motion
- 5 Imperfections and resonances
- 6 Chromaticity
- 7 Longitudinal beam dynamics
- 8 Image and space-charge forces (transverse)
- 9 Coherent instabilities
- 10 Radiating particles
- 11 Diagnosis and compensation
- 12 Special aspects of circular colliders
- Appendix A Transverse particle motion in an accelerator
- Appendix B Accelerator magnets
- Appendix C Closed orbits
- Appendix D Phase equation
- Appendix E Vlasov equation
- References
- Index
Summary
A charge that is being accelerated radiates photons. In any kind of accelerator, the radiation due to the longitudinal acceleration is negligible. However, this is not always true for the radiation due to the transverse acceleration which is imposed by the guide field in circular machines. High-energy electron storage rings, for example, suffer severely from this fundamental energy loss by radiation and it is this fact that makes linear colliders the favoured electron machines of the future. While energy loss by radiation is a problem when considering the efficiency of an accelerator or the background caused in experimental physics detectors, it nevertheless does have certain redeeming features. Being a dissipative force, it is not Liouvillian and it is possible to exploit this to decrease the longitudinal and transverse phase space areas occupied by the beam. It can also provide some stabilisation against coherent oscillations. Best of all, this unwanted energy loss, or synchrotron radiation as it is called, can be turned into an intense source, which is typically in the visible to X-ray region with good directional properties and a well-defined polarisation. Accelerators dedicated to producing this radiation are called synchrotron light sources or simply light sources. Light sources have proved to be extremely valuable research tools and are a rapidly growing branch of the accelerator family.
The history of synchrotron radiation, with the theoretical and experimental development starting with Maxwell, can be found in a very readable account by Blewett.
- Type
- Chapter
- Information
- The Principles of Circular Accelerators and Storage Rings , pp. 220 - 251Publisher: Cambridge University PressPrint publication year: 1993