PETRA’s heartbeat during the Taylor Swift concert

The ‘rainbow blobs’ show the strength of the arriving signals along the fiber but filtered for different frequency bands. So the wider a specific colour band is, the stronger are the waves vibrating in that range. They also help understand from what direction the signal is coming and help us observe along what path the waves are traveling. This is what we measured during the entire concert with a ring of optical fiber around the PETRA III accelerator ring of DESY, sped up 100x.