The H1 Detector

Yesterday I took a walk through the HERA tunnel from the east hall to the north hall, where the deinstallation of H1 is in progress. H1 was one of the two collider experiments installed at DESY's Hadron Electron Ring Accelerator. The original plan was to name the two big HERA experiments H1 and H2, but surprisingly the other collaboration rejected the name H2 and decided that they would prefer the name "ZEUS", which is an acronym for "Zero Experience with Uranium and Scintillators". ;-)

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.