HERA's execution

Yesterday night, after 17 years of operation and 15 years of data taking DESY's HERA accelerator in Hamburg, Germany, was switched off finally. Thousands of phycisists crowded the control rooms and marquees to watch the last beam ever being dumped. In the HERMES control room we got a phone call by BKR (Beschleuniger-Kontrollraum) which informed us that the last beam EVER will be dumped at 23:30h sharp. Everyone was waiting for the big moment and staring at screens.

And then they lost the positrons 10 minutes before.