Advanced Photon Source

An Office of Science National User Facility

Lesson Module A-5: Functional Description of APS Front Ends


This learning module describes the components used in both the bending magnet and insertion device front ends. Front End is defined and put into perspective with the storage ring and the experiment hall beam line that follows.

Lesson Module A-1 provided an abbreviated description of the overall APS facility. The material that is provided by Lesson Module A-1 remains sufficient for the continuation of our studies. In that module, some mention was made of the bending magnets and insertion devices. Without fully describing either of these components, each are involved in the generation of synchrotron radiation. It is the synchrotron radiation that is transported to the experiment hall enclosures and subsequently used for experiments.

The Front End (FE) collectively refers to the hardware that exists between the Storage Ring (containing orbiting electrons) and the x-ray beam line. The Front End begins as a hardware structure tangential to the storage ring, where control of the synchrotron radiation initially takes place. Of course, the Front End must be housed within the Storage Ring tunnel. Because of the geometric properties of the radiation produced by either insertion devices or bending magnets, fundamental differences exist between the Front Ends for the ID beamlines and those for the BM beamlines. The ID Front End components are designed for the most critical wiggler (this device may be considered similar to the undulator for our purposes at this time) beam size and for the highest heat flux levels of the APS undulators. This is necessary in order to accommodate the variation in the radiation properties produced by these devices. Our tutorial begins with discussion of an insertion device beam line, and then will continue with the bending magnet line. Whenever possible, alarm features pertinent for a component are identified. The following is excerpted from the referenced document TB-5.


Contact Patti Pedergnana or Nena Moonier for information or problems relating to this web page.