Project :
Particle radiography of high energy density plasmas
Supervisors: M. Borghesi (QUB), M. Hill (AWE plc)
The following studentship is available through a Business Alliance Award partly funded by the
Department of Education and Learning (DEL) and partly by an industrial sponsor (AWE plc), and
offers an enhanced PhD stipend (3.5 years duration).
Project background and description: The project is aimed to the application of laser-driven, particle
radiography techniques to the investigation of a range of laser-matter interaction conditions of
relevance to fundamental plasma physics, to schemes for energy production via thermonuclear fusion
(Inertial Fusion Energy, IFE), and to laboratory-based studies of astrophysical phenomena. The
extreme concentration of energy in the focal spot of an intense laser on a solid surface leads to the
creation of plasma states characterized by very high energy density, which are inherently difficult to
characterize and diagnose.
Important information on these phenomena has been obtained in recent years by employing
radiographic techniques based on the use of beams of multi- MeV laser accelerated ions as a particle
probe. Methods of ion acceleration employing high power lasers can lead to the generation of beams of
high-energy protons (typically tens of MeV energies), with unique spatial and temporal emission
properties, which make these beams a uniquely powerful tool for radiography of high density plasmas.
In particular, by monitoring the deflection encountered by the protons, one can reconstruct threedimensional, time-resolved maps of the electric and magnetic fields present in the plasma. This offers
unique opportunities for investigating self-generation of large electric and magnetic fields, which are a
very important intrinsic feature of the dynamics of these plasmas: the fields arise from currents either
associated to the thermal expansion of the plasma or to the motion of highly energetic particles (hot
electrons) directly energized by the laser radiation. Such large fields have connections to a broad range
of plasma phenomena including formation of jets, particle acceleration, and filamentation, which are of
relevance to areas such as Inertial Confinement Fusion and Laboratory astrophysics.
AWE plc has recently developed the ORION laser facility , the largest laser system in the UK, and
one of the major systems internationally, which is used to conduct research into high energy density
physics phenomena. The experimental research related to this project will be partly carried out on this
system, as well as on other UK facilities, such as the VULCAN laser at the Rutherford Appleton
Laboratory (Oxford), and the TARANIS facility at QUB.
The full award is available to UK nationals, and will pay full fees and an enhanced stipend of ~ £
17,200 per annum. Candidates should hold the equivalent of a 1st class or 2:1 Honours degree in
physics or a related subject. Preference will be given to candidates with a Master degree.
How to apply:
Applications
must
be
made
through
the
University
electronic
website
at
https://dap.qub.ac.uk/portal/user/u_login.php . Applicants are strongly advised to first contact the
project supervisor (m.borghesi@qub.ac.uk) For any other information or details on the project please
also contact the supervisors. For any other information or details on the project please also contact
the supervisor.
Closing date: 13 February 2015
References:
A.Macchi, M.Borghesi and M. Passoni, Ion acceleration by superintense laser-plasma interaction,
Rev. Mod. Phys., 85, 751 (2013)
H. Ahmed, M. E. Dieckmann, L. Romagnani, D. Doria, G. Sarri, M. Cerchez, E. Ianni, I. Kourakis, A.
L. Giesecke, M. Notley, R. Prasad, K. Quinn, O. Willi, and M. Borghesi, Time-resolved
characterization of the formation of a collisionless shock, Phys. Rev. Lett., 110, 205001 (2013)
K. Quinn, M. E. Dieckmann, L. Romagnani, B. Ramakrishna, G. Sarri, P. A. Wilson, J. Fuchs, L.
Lancia, A. Pipahl, T. Toncian, O. Willi, R.J. Clarke, M. Notley, A. Macchi, and M. Borghesi, Weibelinduced filamentation during an ultrafast, laser-driven plasma expansion, Phys. Rev. Lett., 108,
135001 (2012)
G.Sarri, C. A. Cecchetti, R. Jung, P. Hobbs. S. James, J. Lockyear, R.M. Stevenson, D. J. Hoarty, O.
Willi, M. Borghesi, Spatially resolved measurements of laser filamentation in long scale length
underdense plasmas with and without beam smoothing, Phys. Rev. Lett., 106, 095001 (2011)