The University of Bonn operates the Electron Stretcher Accelerator facility (ELSA) which provides polarized and unpolarized beams up to an energy of 3.5 GeV. ELSA offers two beam areas which are equipped with photon tagging systems. The groups at ELSA have a long experience in the development and operation of complex detector systems. The two major experimental devices are the combination of the detectors Crystal Barrel/TAPs (CB) and the combination of the detectors BGO/Open Dipole (BGO-OD).

UBO has specific roles in JRA7-HaSP, JRA10-CryPTA, JRA13-P3E and JRA14-MPGD_HP.

UBO has the responsibility of TA4-ELSA (Hartmut Schmieden), JRA10-CryPTA (Hartmut Dutz) and JRA14-MPGD_HP (Bernhard Ketzer, Fulvio Tessarotto).

EC funds in TA4-ELSA, JRA7-HaSP, JRA10-CryPTA and JRA14-MPGD_HP.