Plasma wakefield acceleration - bridging fund
Lead Research Organisation:
Imperial College London
Department Name: Physics
Abstract
A request is made for bridging AWAKE-UK for the period 1 October 2014 - 30 September 2015, restricting to a flat-cash continuation as recommended. This allows us to maintain our effort in the currently funded areas although for delivery and continued leadership, a more significant grant will be requested after the outcome of the accelerator review is known. During the bridging period, PDRAs currently in post will be retained, with other resources used for essential consumables and travel to attend Collaboration Meetings and visits primarily to CERN.
Imperial will work on WP4: Plasma Discharge Source. A summary of the objectives are given below:
2.4 WP4 : Discharge plasma source
Along with the metal vapour and helicon sources, the discharge plasma cell is one of the tech- nology options for AWAKE as described in the Design Report. The discharge cell has significant advantages over the other two, viz. it is scalable to long distances (i.e. tens of metres and beyond) which is not the case for the metal vapour cell, and although the helicon is similarly scalable, this is a far more expensive option than the discharge source due to the large amounts of RF needed to generate the helicon waves. The simple, glass-tube structure of the discharge cell should also make it more amenable to diagnostic devices (e.g. WP2) which can utilise the open structure of the discharge cell. The work is led by Imperial, with Nelson Lopes the AWAKE task leader, in collaboration with Lisbon. During the current grant, prototypes have been built, with a 10mm diameter 1.5m long cell operated at ~0.3Hz based on a 1.6 microsecond pulsed electrical discharge that provides ~300 A at 2 kV. The power supply is based on a prototype built in-house at Imperial. Measurements of the density uniformity using interferometry are now underway which after completion should demonstrate the feasibility of these discharges in a configuration close to the that needed for AWAKE. Longer cells are also in preparation.
The key issues to be worked on during the next year are:
* Obtain gas pressure stability in the glass tube;
* Obtain the required plasma uniformity;
* Measure the required plasma density;
* Ensure HV setup reliability;
* Comply with CERN standards;
* Development of longer (up to 10 m) prototypes.
Imperial will work on WP4: Plasma Discharge Source. A summary of the objectives are given below:
2.4 WP4 : Discharge plasma source
Along with the metal vapour and helicon sources, the discharge plasma cell is one of the tech- nology options for AWAKE as described in the Design Report. The discharge cell has significant advantages over the other two, viz. it is scalable to long distances (i.e. tens of metres and beyond) which is not the case for the metal vapour cell, and although the helicon is similarly scalable, this is a far more expensive option than the discharge source due to the large amounts of RF needed to generate the helicon waves. The simple, glass-tube structure of the discharge cell should also make it more amenable to diagnostic devices (e.g. WP2) which can utilise the open structure of the discharge cell. The work is led by Imperial, with Nelson Lopes the AWAKE task leader, in collaboration with Lisbon. During the current grant, prototypes have been built, with a 10mm diameter 1.5m long cell operated at ~0.3Hz based on a 1.6 microsecond pulsed electrical discharge that provides ~300 A at 2 kV. The power supply is based on a prototype built in-house at Imperial. Measurements of the density uniformity using interferometry are now underway which after completion should demonstrate the feasibility of these discharges in a configuration close to the that needed for AWAKE. Longer cells are also in preparation.
The key issues to be worked on during the next year are:
* Obtain gas pressure stability in the glass tube;
* Obtain the required plasma uniformity;
* Measure the required plasma density;
* Ensure HV setup reliability;
* Comply with CERN standards;
* Development of longer (up to 10 m) prototypes.
Planned Impact
The main academic beneficiaries are the high-energy physics community, that will be able to assess if there is sufficient expertise to be able to plan and implement proton drive plasma wakefield experiments, that have the possibility of overcoming the energy barrier for electron-positron colliders.
Publications
Assmann R
(2014)
Proton-driven plasma wakefield acceleration: a path to the future of high-energy particle physics
in Plasma Physics and Controlled Fusion
Bracco C
(2016)
AWAKE: A Proton-Driven Plasma Wakefield Acceleration Experiment at CERN
in Nuclear and Particle Physics Proceedings
Caldwell A
(2016)
Path to AWAKE: Evolution of the concept
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Gschwendtner E
(2016)
AWAKE, The Advanced Proton Driven Plasma Wakefield Acceleration Experiment at CERN
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Description | Self-modulation of the SPS beam at CERN seen which is due to driving of plasma wave Electron acceleration with the self-modulated beam was also observed, but we were not involved due to lack of funding. |
Exploitation Route | The next stage of the AWAKE experiment is now funded and in preparation. STFC has funded the development of the plasma cells. |
Sectors | Government, Democracy and Justice,Other |
Description | EuPRAXIA |
Amount | £132,142 (GBP) |
Funding ID | 653782 |
Organisation | European Commission |
Department | Horizon 2020 |
Sector | Public |
Country | European Union (EU) |
Start | 11/2015 |
End | 10/2019 |
Description | AWAKE-II |
Organisation | European Organization for Nuclear Research (CERN) |
Country | Switzerland |
Sector | Academic/University |
PI Contribution | Developing plasma cells for longer length plasmas required for AWAKE-II experiment and developing associated diagnostics. |
Collaborator Contribution | Preparation of the SPS beam line for the AWAKE experiment. Recent additions include adding a high performance electron injection beamline. |
Impact | A number of high profile publications have resulted in the AWAKE project though none yet using the new plasma source. |
Start Year | 2013 |
Description | IST AWAKE contribution |
Organisation | University of Lisbon |
Department | Instituto Superior Tecnico |
Country | Portugal |
Sector | Academic/University |
PI Contribution | We are collaborating with Dr Nelson Lopes to develop a next generation plasma cell for the AWAKE-II run. We have built a prototype in the Blackett Laboratory that will be expanded to 10m to be implemented in CERN. We are also contributing with diagnostics of the cell. |
Collaborator Contribution | Dr Lopes was instrumental in the building of the cell, in design for the power supply (which uses solid-state switches to be low power) and in pitching the use of the cell to the AWAKE collaboration. |
Impact | Dr Lopes has obtained seed-corn money from the FCT in Portugal to continue cell development, and we have recently been awarded money in the AWAKE-UK collaboration to build a cell for CERN. |
Start Year | 2012 |
Description | Talk to IC-SW Alumni Association |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | 30-40 IC Alumni interested in research taking place in the University. |
Year(s) Of Engagement Activity | 2019 |
Description | Talk to Imperial College PhysSoc |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Undergraduate students |
Results and Impact | Talked about novel plasma accelerators to undergraduate students, which many reported was the first time they had heard of the concept. |
Year(s) Of Engagement Activity | 2018 |