Beam line
A beam line , beam guide or beam pipe (often also referred to as English beamline in German usage ) is part of an accelerator- physical apparatus that transports the accelerated particles (e.g. electrons or ions ) or e.g. B. the synchrotron radiation generated leads to a point of use - for example an experiment setup. At research reactors and spallation neutron sources , this is the name given to lines for discharged neutron radiation . In the case of high-power lasers , too , where the radiation is guided in a vacuum, the vacuum tube system is referred to as beam lines.
In addition to forwarding, an accelerator beam line can also perform other tasks - such as focusing the radiation. In the case of a linear accelerator , the entire accelerator structure from the particle source is sometimes referred to as the beam line. A beam line typically begins at the particle or radiation source and ends at an experiment, a beam dump or an irradiation site, for example as part of proton therapy . A movable beam guidance in the framework of radiation allows the irradiation of a once-bearing patients from different directions, english gantry called.
In order to achieve a large mean free path and thus not to disturb the beam properties, particle radiation, X-ray radiation and strong laser radiation are often guided in a vacuum . Therefore, beam lines often consist of vacuum tubes. At large, high-energy accelerators, they are often laid underground in tunnels in order to shield undesirable radiation (e.g. bremsstrahlung or other types of radiation, for example if the beam hits the pipe). Various devices can be arranged along the beam line, e.g. B .:
- Vacuum pumps to maintain the vacuum and measuring devices for the vacuum system (e.g. pressure)
- Magnets for beam steering and shaping
- Beam interrupter
- (controllable) apertures.
The following components are also installed, especially with X-ray and laser beam lines:
- distracting and focusing mirrors
- Monochromators
- Apertures and columns
- Radiation detectors.
Individual evidence
- ↑ Example ( Memento from October 29, 2013 in the Internet Archive )
- ^ Research reactor FRM-2 ( Memento from October 5, 2013 in the Internet Archive )
- ↑ CA Haynam, PJ Wegner, JM Auerbach, MW Bowers, SN Dixit, GV Erbert, GM Heestand, MA Henesian, MR Hermann, KS Jancaitis, KR Manes, CD Marshall, NC Mehta, J. Menapace, E. Moses, JR Murray , MC Nostrand, CD Orth, R. Patterson, RA Sacks, MJ Shaw, M. Spaeth, SB Sutton, WH Williams, CC Widmayer, RK White, ST Yang, BM Van Wonterghem: National Ignition Facility laser performance status . In: Applied Optics . tape 46 , no. 16 , 2007, ISSN 0003-6935 , p. 3276 , doi : 10.1364 / AO.46.003276 .
- ↑ Alex Chao, M. Tigner: Handbook of Accelerator Physics and Engineering . World Scientific, Jan. 1, 1999, ISBN 978-981-02-3858-2 , p. 47 (accessed August 30, 2013).