How does BESSY II work?
BESSY II in Berlin-Adlershof is a synchrotron light source. Synchrotron light results whenever electrons are accelerated to near the speed of light and are forced to travel in a circle. In the process, they tangentially emit photon packets or light pulses. The wavelengths range from terahertz to visible light all the way to hard X-rays.
With the help of electromagnetic elements (undulators, wigglers, hollow space resonators), the BESSY II accelerator experts are able to increase intensity to an extreme.
Educational material (in English): http://www.lightsources.org/educational-material
FAQ's BESSY II
How many electrons are stored in the ring?
Between one and about 1000 billion in max 400 packages, usually 360 packages.
How long does an electron need for a circuit?
800 nanoseconds, that’s less than a millionth of a second.
How long does an electron stay in the ring?
For up to 10 hours. In that time it travels about 75 times the distance between the sun and the earth.
How bright is the light?
The fine beam is a million times brighter than a fine ray from the sun.
How long is the flash of light?
About 20 picoseconds.
How high is the vacuum?
The residual pressure is about 10-10 millibar (mbar), nearly as good as between the earth and moon. This would be equivalent to 1 cubic centimeters (cc) of air distributed in ninety BESSY halls.
How much electricity does BESSY II consume?
In normal mode BESSY II needs about 2.7 Megawatt (MW). This is equivalent to about 8.000 two-person households. The maximum power draw is 5 Megawatt (MW) – an ICE needs about 6 Megawatt (MW) to start up.