Nitrogen tank for the accelerator project bERLinPro was installed in Adlershof

Spectacular delivery and installation; all pictures (excl. no 4 and 7) made by HZB/W. Anders

The tank is slowly and carefully set upright by two cranes.

Photo: HZB/J. Bierbaum

The nitrogen tank is then bolted to the ground.

With the tank now anchored down, the iron chains are removed.

View inside the new accelerator hall for bERLinpro where the components are gradually being installed during the next months (pictured is the magnet section). Photo: HZB/M.Setzpfand

Rising 18 metres into the air, the nitrogen tank on the Helmholtz-Zentrum Berlin campus in Adlershof was installed on 18 July 2017. It can store up to 80 cubic metres of liquid nitrogen. This nitrogen will be used for pre-cooling the cooling system which is necessary for operating the new energy recovery linear accelerator (bERLinPro). The HZB experts are currently setting up a prototype for testing the potential of this accelerator technology.

The nitrogen tank was brought to Berlin by on a 25 metre long heavy-duty transporter from Děčín (Czech Republic) and then erected with two cranes. Our colleague Roswitha Schabardin describes the spectacular event in our blog.

The researchers are constructing a test facility on the Adlershof campus: a prototype of a linear accelerator that can recover the energy of the accelerated particles (bERLinPro). In it, a tremendous amount of energy is used to accelerate electrons to near light speed. In this state, the electrons give off extremely high quality X-ray light that is of great use for research purposes. After running through a high speed circuit, the electrons in bERLinPro will then be recaptured and their energy recovered.

To make bERLinPro a reality, the HZB researchers have to develop entirely novel components and test them out in the newly built accelerator hall. Operating bERLinpro requires an extremely complex infrastructure, which is being set up piece by piece in the hall. One of the requisite components is a sophisticated cooling system. The superconducting niobium cavities have to be cooled down to the lowest temperature possible using helium.

Getting the system to such a low temperature using helium alone would be too expensive, so liquid nitrogen is used to pre-cool it first. This nitrogen is now stored in the new 80 cubic metre tank. “We expect to consume about one truckful of liquid nitrogen a week,” says supervising engineer Jochen Heinrich.

The cooling system will be completed over the next few months. This includes relocating the helium cooling system in autumn 2017 from the heavy-duty hall to the new technical building located alongside the underground accelerator hall.