The shell for the bERLinPro building – the test facility for an energy-recovery linear accelerator at Helmholtz-Zentrum Berlin – is now complete. The extremely complex structure was erected at the Wilhelm Conrad Röntgen Campus of HZB in Berlin-Adlershof in just ten months. The topping-out ceremony took place on July 27, 2016 at 13:00 in the presence of construction firms, guest VIPs, and HZB staff.

“bERLinPro will be a unique research instrument with which we will enter completely new territory in accelerator technology”, says Prof. Andreas Jankowiak, head of the HZB Institute for Accelerator Physics and the bERLinPro project. This involves the prototype of an energy-recovery linear accelerator in which electrons will be accelerated with large amounts of energy to nearly the speed of light. Electrons in this state emit high-quality X-rays that are very important for research purposes. After passing through the high-speed sections of bERLinPro, the electrons will be captured again and their remaining energy recovered.

“To realise bERLinPro, we first need to develop the various components and methods, and then test them in the new accelerator hall”, explains Prof. Jens Knobloch, head of the SRF - Science and Technology Institute that has a major role in the development of bERLinPro. “A rather complex infrastructure is necessary for this.”

The construction of the hall has therefore been a demanding project. “The planners needed to take into account the demands for increased radiation protection and statics, for example. For this reason, just the erection of the structural shell represented an enormous challenge for the companies participating in the construction and their staffs. Not least of which was realisation of the operational infrastructure, such as guarantying proper operation of the cooling system for the superconducting test accelerator that will be tackled next”, elaborated Dr. Birgit Schröder-Smeibidl, head of the HZB Facility Management division, under whose supervision the hall has been constructed.

Constanze Tibes, the architect for the building (DGI-Bauwerk architectural GmbH), added: “There was no other building we could take as an example for the hall and planning was very time-consuming. We have erected here a unique structure for serving science.”

“Completing this work in such a short time was only feasible because all those involved have worked together in an outstanding manner”, emphasised the engineer responsible for the project at HZB, Oliver Schüler. “Communications were superb and enabled us to adhere to all the scheduling and cost projections.”

A number of the components that have been developed for bERLinPro can be incorporated for use in the BESSY II electron storage ring. This is the case for example of the high-current superconducting cavity resonators that accelerate the electrons. They are the centrepiece of BESSY-VSR, the variable pulse-length storage ring that BESSY II will be converted into next.

While packets of electrons of only a particular duration circulate in BESSY II, researchers want to simultaneously utilise both long and short-duration packets of electrons in BESSY-VSR to create long and short pulses of light within the same ring. “The synergies between the two projects will begin to benefit the future users of BESSY-VSR during the period when we are still preparing components in the test facility for deployment in bERLinPro”, confirms Prof. Anke Kaysser-Pyzalla, Scientific Director of HZB: “Researchers, in particular those who depend on short pulses, are enthusiastic about our design for BESSY-VSR and the advantages that bERLinPro development will introduce.