Plasma wakefield acceleration driven by charged particle bunches and the AWAKE experiment at CERN
Event details
| Date | 08.06.2015 |
| Hour | 10:30 › 11:30 |
| Speaker | Prof. P. Muggli, Group Leader – Future Accelerators Group, Max-Planck-Inst. für Physik, Münich, D |
| Location |
PPB 019
|
| Category | Conferences - Seminars |
The AWAKE[1] experiment aims at exploring the use of proton bunches as drivers for plasma wakefields. Proton bunches are interesting because they carry large amounts of energy (10-100kJ) so that they can drive wakefields over long distances and lead to very large energy gain by externally injected particles [2]. Proton bunches from the CERN super proton synchrotron (SPS) with 400GeV/particle are long (~12cm or 400ps rms). In order to drive ~GV/m the bunch needs to be ~1mm long, the wavelength λpe of the relativistic plasma wake in a plasma with electron density in the (1-10)x1014cm-3 range. However, long bunches propagating in dense plasmas are subject to the self-modulation instability (SMI). The SMI modulates the bunch density at ~λpe. The long and modulated bunch then resonantly drives wakefields to large amplitude.
In the AWAKE experiment a short laser pulse abruptly creating the plasma within the proton bunch seeds the SMI. We are developing various diagnostics based on incoherent optical transition radiation (OTR) and its coherent variation CTR to measure the characteristics (period, etc) of the proton bunch modulation resulting from the SMI occurrence. The first phase of the experiment will be devoted to the study of the SMI. After this first phase, scheduled to start at the end of 2016, a long electron bunch from an external source will be injected to sample the accelerating fields. An energy gain on the order of 1GeV over the 10-m-long plasma length is expected. Later experiment will study accelerator physics issues, such as injection of a short electron bunch (possibly from another plasma-based accelerator), beam loading and large energy gains. Long terms projects include development of very long plasma sources, generation of single, short proton bunches and application of the scheme to high-energy physics.
I will give an introduction to charged particle beam driven, plasma wakefield acceleration and show latest experimental results. I will describe the AWAKE experiment at CERN, the first and only one using proton bunches to drive wakefields in plasma.
1. Proton-driven plasma wakefield acceleration: a path to the future of high-energy particle physics , AWAKE Collaboration, Plasma Phys. Control. Fusion 56 084013 (2014).
2. Proton-driven plasma-wakefield acceleration, A. Caldwell et al., Nature Physics 5, 363 (2009).
In the AWAKE experiment a short laser pulse abruptly creating the plasma within the proton bunch seeds the SMI. We are developing various diagnostics based on incoherent optical transition radiation (OTR) and its coherent variation CTR to measure the characteristics (period, etc) of the proton bunch modulation resulting from the SMI occurrence. The first phase of the experiment will be devoted to the study of the SMI. After this first phase, scheduled to start at the end of 2016, a long electron bunch from an external source will be injected to sample the accelerating fields. An energy gain on the order of 1GeV over the 10-m-long plasma length is expected. Later experiment will study accelerator physics issues, such as injection of a short electron bunch (possibly from another plasma-based accelerator), beam loading and large energy gains. Long terms projects include development of very long plasma sources, generation of single, short proton bunches and application of the scheme to high-energy physics.
I will give an introduction to charged particle beam driven, plasma wakefield acceleration and show latest experimental results. I will describe the AWAKE experiment at CERN, the first and only one using proton bunches to drive wakefields in plasma.
1. Proton-driven plasma wakefield acceleration: a path to the future of high-energy particle physics , AWAKE Collaboration, Plasma Phys. Control. Fusion 56 084013 (2014).
2. Proton-driven plasma-wakefield acceleration, A. Caldwell et al., Nature Physics 5, 363 (2009).
Practical information
- Informed public
- Free
Organizer
- Prof. P. Ricci
Contact
- Prof. P. Ricci