Accelerator Test Facility and Synchrotron Radiation Source at KIT

EuroCirCol: A key to New Physics

  • Date: June 2015


Monday 1 June saw the start of EuroCirCol, the EC-funded part of the FCC study that will develop the conceptual design for an energy-frontier hadron collider.

The EuroCirCol kick-off event at CERN on 2 to 4 June brought together 62 participants to constitute governance bodies, commit to the project plan and align the organisation, structures and processes of 16 institutions from 10 countries.

The goal of the project is to conceive a post-LHC research infrastructure around a 100 km circular energy-frontier hadron collider capable of reaching 100 TeV collisions. The project officially started on 1 June and will run for four years. The total estimated budget of 11.2 MEUR includes a 2.99 MEUR contribution from the Horizon 2020 programme on developing new world-class research infrastructures.

EuroCirCol will deliver a design for a hadron collider as part of the broader Future Circular Collider (FCC) study. It will provide input to an accelerator infrastructure roadmap taking into account European and global interests by the time of the next update of the European Strategy for Particle Physics in 2018. It was the only one of 39 submissions to receive the maximum number of points from reviewers, a clear sign that high-energy physics remains a top priority for the European Commission.

EuroCirCol is organised around four technical work packages: the first two relate to the development of the collider’s lattice and beam optics, including the experimental regions. A third is for the development of prototypes and will test a novel cryogenic beam vacuum system that can respond to the challenges of the high synchrotron radiation expected at such a collider. This work also pioneers collaboration between the particle physics light source communities, with opportunities to improve existing synchrotron radiation facilities and to reduce the cost and improve performance of fourth- or fifth-generation light sources. The last work package will study a viable design for a 16 Tesla accelerator magnet as part of a worldwide study of conductor R&D for the HL-LHC project and the FCC study.

The EuroCirCol project creates opportunities for doctoral and post-doctoral assignments in the areas of beam optics and accelerator technologies in the participating institutes. It also provides excellent training opportunities for next-generation accelerator physicists under the guidance of world-renowned experts in the field.

EuroCirCol is a building block in the globally coordinated strategy of the FCC study to produce a global design for a global machine. The main outcome of EuroCirCol will be the laying of foundations for subsequent research infrastructure development that will strengthen Europe as a leader in global research cooperation over the coming decades.

Johannes Gutleber, CERN



In the FCC, significant synchrotron radiation power will be generated and will impact on the cryogenic beam vacuum chamber of the 100 km circular accelerator, thus influencing the 100 TeV beam’s stability and lifetime.

Cryo Beam Vacuum

Therefore an important part of the EuroCirCol study includes the design and construction of a complete cryogenic beam pipe system as a prototype.

The expected synchrotron radiation spectrum of FCC is a close match to that provided by the synchrotron light source ANKA, making it an ideal choice to test this system at Karlsruhe Institute of Technology (KIT), Germany.


Today, no quantitative  performance model is available for a 100 TeV beam, that can describe the vacuum  dynamics  in presence  of  high-power  synchrotron  radiation  and  the anticipated beam  power. Calculations enter a new frequency domain because of the intrinsically low revolution frequency due to the dimension of the 100 km ring circumference. The dynamic behaviour of the vacuum surrounding the high energy particle beam, the need to understand electron and ion cloud effects and to develop an “Ansatz” for feedback and impedance mitigation measures, are pioneering studies. Up to date, no experimental test have been performed to derive or verify models. In order to avoid instabilities of the accelerated beams and to reduce the beam heat load to the vacuum chamber, this must be designed to keep the ultrahigh vacuum while maintaining the impedance as well as the photon and electron desorption of the gas molecules on the surface of the vacuum chamber walls to small values.  To address these challenges, the photon and electron desorption will be studied by illuminating different vacuum chambers  with a realistic energy spectrum at the synchrotron light source ANKA at KIT in the framework of this FCC study.

Anke-Susanne Müller, KIT