The beam position monitors, that measure the position of the electron beam at 5,000 times per second (5 kHz), detected a sudden movement of the electron beam at 01:38, corresponding with the earthquake registered one minute before at the area of Alt Empordà (Catalonia). The magnitude-4.3 earthquake caused beam oscillations of 800 nanometres, from peak to peak.
This is possible thanks to the great stability of the electron beam generated at ALBA. In natural conditions, the electron beam has oscillations below 100 nanometres because of the orbit feedback system that corrects the electron beam orbit. This feedback system, working at 5 kHz, started operation in ALBA in May 2014, increasing by a factor of 10 the stability of the photon beam reaching the sample.
In September 2015, even though there is a distance of 11,000 kilometers, the ALBA facility also registered the earthquake happening in Chile. The signal was detected approximately at 2 AM, one hour later of the earthquake, being that period the time needed for the seismic waves to go through the inner core of the Earth, from Chile to ALBA.
Graphic showing oscillations at the electron beam during the 29th October (in blue) and the earthquake in Chile in September (in green).
