Equipment installed in a tunnel
Downstream end of the plasma source and instrumentation. (Image: CERN)

The Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) is an accelerator R&D project based at CERN. It investigates the use of plasma wakefields driven by a proton bunch to accelerate charged particles.

A plasma wakefield is a type of wave generated by particles travelling through a plasma. AWAKE sends proton beams through plasma cells to generate these fields. By harnessing wakefields, physicists may be able to produce accelerator gradients hundreds of times higher than those achieved in current radiofrequency cavities. This would allow future colliders to achieve higher energies over shorter distances than is possible today.

AWAKE uses proton beams from the Super Proton Synchrotron (SPS). These protons are injected into a 10-metre plasma cell to initiate strong wakefields. A second beam – the “witness” electron beam – is then accelerated by the wakefields, gaining up to several gigavolts of energy. Following AWAKE's approval in autumn 2013, the first proton beams were sent to the plasma cell at the end of 2016. During the 2016–2017 run, strong wakefields generated by the proton beams in plasma were observed for the first time and studied in detail. In 2018, AWAKE demonstrated for the first time the acceleration of electrons to multi- GeV energy levels in these plasma wakefields.

The second phase of AWAKE successfully started in 2021 and now runs for several years. Its goal is to bring the research and development of proton driven plasma wakefield acceleration to a point where particle physics applications could be proposed. To this aim, AWAKE will demonstrate the acceleration of electrons to several GeVs while preserving the beam quality as well as the scalability of the experiment.

AWAKE is the world’s first proton-driven plasma wakefield acceleration experiment. Besides demonstrating how protons can be used to generate wakefields, AWAKE will also develop the necessary technologies for long-term, proton-driven plasma acceleration projects.

AWAKE is an international scientific collaboration made up of 23 institutes and involving over 90 engineers and physicists (May 2023).

AWAKE project leader, Edda Gschwendtner, presents her ideas on how the concept of ‘surfing’ wakefields could be used to create smaller accelerators in the future at TEDxCERN in 2015 (Video: TEDx)