Beam Position Monitors

Among the greatest challenges of the diagnostic system is the design and fabrication of electron beam position monitors, as the precision of the measurement of the beam position must be in the order of tenths of micrometers and the measurement cannot disturb the stored beam. The electronic monitors must have temporal resolution for package position measurements at each turn in the ring (measures back-to-back position), which means about 500,000 precise measurements of the position every second.

The specifications for the stability of the synchrotron light source require a Beam Position Monitor that presents stability levels below 10% of the size of the beam being monitored, i.e., the monitor can only move, either slowly or quickly, less than 100 nm, which means stability better than 0.0001 mm. Temperature variations of the order of one tenth of a degree or mechanical vibrations of the soil and mechanical parts near the monitor can easily deteriorate its mechanical stability.