Laboratory Simulation of Magnetized Plasma Turbulence in the Intergalactic Medium
Lead Research Organisation:
University of Oxford
Department Name: Oxford Physics
Abstract
We propose an experimental programme to probe one of the greatest puzzles of modern astrophysics: the generation and amplification of magnetic fields ubiquitously found in the Universe. The aim is to demonstrate amplification of magnetic fields by turbulent dynamo - a great challenge of modern experimental plasma physics. We will also study the distribution of turbulent energy between velocity, magnetic and density fluctuations, providing a comprehensive experimental characterisation of the energy cascade in a turbulent plasma.
Magnetic fields are ubiquitously observed in the Universe. Their energy density is comparable to the energy density of the mean plasma flows, so the magnetic fields are essential players in the dynamics of the luminous matter. The total magnetic energy represents a sizable fraction of the cosmic energy budget. What is the origin of these fields? The fact that they are ubiquitous, stochastic and dynamically strong suggests that a universal physical mechanism is at play. The most popular scenario of the cosmic magnetogenesis is that the field grows via some form of turbulent dynamo - fast (exponential) amplification of stochastic field by turbulent motions into which it is embedded, starting from an initial small seed. Understanding magnetogenesis is part of the broader challenge of understanding cosmic turbulence, and the way different form of energies (thermal, turbulent, magnetic) are partitioned on various scales.
With the advent of high-power lasers, a new field of research has opened where, using simple scaling relations, astrophysical environments can be reproduced in the laboratory. The similarity is sufficiently close to make such experiments of high interest. Here we propose to establish an experimental platform using laser-produced plasmas where magnetic fields are produced and amplified by turbulence. In the turbulent plasma, small magnetic fields are initially generated by electrical currents resulting from mis-aligned density and temperature gradients - the so-called Biermann battery effect. By then characterizing the properties of such plasmas and the embedded magnetic fields, we intend to show that those tiny fields can be amplified to much larger values, and up to equipartition with the kinetic energy of the turbulent motions. We will use these experiments to measure the magnetic-energy, density and velocity spectra in the turbulent plasma, thus addressing the details of the energy cascade. Thus, our work would establish, for the first time experimentally, the soundness of the theoretical expectation that tiny seeds produced at protogalactic structures (~10^-21 G) can be amplified to observed dynamically significant values (~10^-6 G) in cosmologically short times.
Magnetic fields are ubiquitously observed in the Universe. Their energy density is comparable to the energy density of the mean plasma flows, so the magnetic fields are essential players in the dynamics of the luminous matter. The total magnetic energy represents a sizable fraction of the cosmic energy budget. What is the origin of these fields? The fact that they are ubiquitous, stochastic and dynamically strong suggests that a universal physical mechanism is at play. The most popular scenario of the cosmic magnetogenesis is that the field grows via some form of turbulent dynamo - fast (exponential) amplification of stochastic field by turbulent motions into which it is embedded, starting from an initial small seed. Understanding magnetogenesis is part of the broader challenge of understanding cosmic turbulence, and the way different form of energies (thermal, turbulent, magnetic) are partitioned on various scales.
With the advent of high-power lasers, a new field of research has opened where, using simple scaling relations, astrophysical environments can be reproduced in the laboratory. The similarity is sufficiently close to make such experiments of high interest. Here we propose to establish an experimental platform using laser-produced plasmas where magnetic fields are produced and amplified by turbulence. In the turbulent plasma, small magnetic fields are initially generated by electrical currents resulting from mis-aligned density and temperature gradients - the so-called Biermann battery effect. By then characterizing the properties of such plasmas and the embedded magnetic fields, we intend to show that those tiny fields can be amplified to much larger values, and up to equipartition with the kinetic energy of the turbulent motions. We will use these experiments to measure the magnetic-energy, density and velocity spectra in the turbulent plasma, thus addressing the details of the energy cascade. Thus, our work would establish, for the first time experimentally, the soundness of the theoretical expectation that tiny seeds produced at protogalactic structures (~10^-21 G) can be amplified to observed dynamically significant values (~10^-6 G) in cosmologically short times.
Planned Impact
With the need of reduction in carbon footprint, fusion energy may represent a long-term goal for a sustainable and clean form of energy. The knowledge basis that our project produces is at the root of fusion energy, and applicable to either inertial or magnetic confinement schemes. The expertise gained in conducting the research work has broad relevance to the development of advanced (and clean) energy sources, and it will lead to enabling critical sciences and technologies in the short term. These will include the capability of performing experiments at fusion-scale laser facilities and the development of advanced diagnostics involved in inertial confinement fusion research. We are training the next generation of scientists that will eventually lead the technical realization of a fusion power plant. In this sense, it is indicative the National Ignition Facility laser, where we have proposed our flagship experiments, has, as its core mission, the technical demonstration of inertial fusion energy. In this context, we will introduce the PDRA to the wider energy network in Oxford (http://www.energy.ox.ac.uk), by participating in open discussions on public and regulatory acceptance of fusion energy - which is carried through diverse disciplines ranging from politics, law, science and engineering.
Laser-plasma experiments, shocks and turbulence are relevant to the UK nuclear defense programmes, both because they provide knowledge on related physics, but also (and more importantly so) because they increase the user base for the AWE Orion laser facility with a larger pool of scientists trained in high energy density science. The fact that one of our collaborators (Dr Foster) is affiliated with AWE confirms the strategic interest in the research topics of this proposal. The PDRA trained on this grant will gain relevant skills enabling him/her to either continue with academic jobs or to gain employment in (defense) national laboratories. Indeed, our former students and PDRAs have moved to positions in academia, national laboratories, and industry - particularly an Oxford-based spin-off company (Oxyntix) focused on the exploitation of fusion energy for commercial purposes.
In addition to publishing our results in high profile journals, we expect that our work will be of large interest for the public understanding of science. Our previous experimental work has received considerable impact on the general public media, with news coverage on Discovery News, CERN Courier and the Daily Mail. We expect the same will occur with the work proposed here. Proposed activities will include visit to local schools and a dedicated web page. The physics department at Oxford University has already a dedicated staff member (an outreach officer) that would help us in coordinating our outreach activities through the network of schools that are part of the Oxford University outreach program. We envision that our PDRA will engage with teachers and schools, about once a year. Our outreach web page will also be linked to the university's resources such as http://www.oxfordsparks.net/subjects which is specifically catered to public engagement.
Laser-plasma experiments, shocks and turbulence are relevant to the UK nuclear defense programmes, both because they provide knowledge on related physics, but also (and more importantly so) because they increase the user base for the AWE Orion laser facility with a larger pool of scientists trained in high energy density science. The fact that one of our collaborators (Dr Foster) is affiliated with AWE confirms the strategic interest in the research topics of this proposal. The PDRA trained on this grant will gain relevant skills enabling him/her to either continue with academic jobs or to gain employment in (defense) national laboratories. Indeed, our former students and PDRAs have moved to positions in academia, national laboratories, and industry - particularly an Oxford-based spin-off company (Oxyntix) focused on the exploitation of fusion energy for commercial purposes.
In addition to publishing our results in high profile journals, we expect that our work will be of large interest for the public understanding of science. Our previous experimental work has received considerable impact on the general public media, with news coverage on Discovery News, CERN Courier and the Daily Mail. We expect the same will occur with the work proposed here. Proposed activities will include visit to local schools and a dedicated web page. The physics department at Oxford University has already a dedicated staff member (an outreach officer) that would help us in coordinating our outreach activities through the network of schools that are part of the Oxford University outreach program. We envision that our PDRA will engage with teachers and schools, about once a year. Our outreach web page will also be linked to the university's resources such as http://www.oxfordsparks.net/subjects which is specifically catered to public engagement.
Publications
Albertazzi B
(2020)
Experimental characterization of the interaction zone between counter-propagating Taylor Sedov blast waves
in Physics of Plasmas
Albertazzi B
(2018)
Experimental platform for the investigation of magnetized-reverse-shock dynamics in the context of POLAR
in High Power Laser Science and Engineering
Albertazzi B
(2022)
Triggering star formation: Experimental compression of a foam ball induced by Taylor-Sedov blast waves
in Matter and Radiation at Extremes
Arrowsmith C
(2021)
Generating ultradense pair beams using 400 GeV / c protons
in Physical Review Research
Bailly-Grandvaux M
(2018)
Guiding of relativistic electron beams in dense matter by laser-driven magnetostatic fields.
in Nature communications
Beyer K
(2018)
Analytical estimates of proton acceleration in laser-produced turbulent plasmas
in Journal of Plasma Physics
Bott A
(2017)
Proton imaging of stochastic magnetic fields
in Journal of Plasma Physics
Bott A
(2022)
Insensitivity of a turbulent laser-plasma dynamo to initial conditions
in Matter and Radiation at Extremes
Bott A
(2021)
Time-resolved turbulent dynamo in a laser plasma
in Proceedings of the National Academy of Sciences
Bott AFA
(2019)
Thomson scattering cross section in a magnetized, high-density plasma.
in Physical review. E
Bott AFA
(2021)
Inefficient Magnetic-Field Amplification in Supersonic Laser-Plasma Turbulence.
in Physical review letters
Casner A
(2018)
Turbulent hydrodynamics experiments in high energy density plasmas: scientific case and preliminary results of the TurboHEDP project
in High Power Laser Science and Engineering
Chen C
(2016)
MULTI-SPECIES MEASUREMENTS OF THE FIREHOSE AND MIRROR INSTABILITY THRESHOLDS IN THE SOLAR WIND
in The Astrophysical Journal
Chen L
(2020)
Transport of High-energy Charged Particles through Spatially Intermittent Turbulent Magnetic Fields
in The Astrophysical Journal
Churazov E
(2016)
Arithmetic with X-ray images of galaxy clusters: effective equation of state for small-scale perturbations in the ICM
in Monthly Notices of the Royal Astronomical Society
Collins GW
(2020)
Role of collisionality and radiative cooling in supersonic plasma jet collisions of different materials.
in Physical review. E
Cross JE
(2016)
Laboratory analogue of a supersonic accretion column in a binary star system.
in Nature communications
Cross JE
(2016)
Theory of density fluctuations in strongly radiative plasmas.
in Physical review. E
Fiuza F
(2020)
Electron acceleration in laboratory-produced turbulent collisionless shocks
in Nature Physics
Gregori G
(2019)
Modified Friedmann Equations via Conformal Bohm-de Broglie Gravity
in The Astrophysical Journal
Ishikawa T
(2016)
Thomson scattering measurement of a collimated plasma jet generated by a high-power laser system
in Journal of Physics: Conference Series
Kasim M
(2019)
Inverse problem instabilities in large-scale modeling of matter in extreme conditions
in Physics of Plasmas
Kasim MF
(2019)
Retrieving fields from proton radiography without source profiles.
in Physical review. E
Kawazura Y
(2019)
Thermal disequilibration of ions and electrons by collisionless plasma turbulence.
in Proceedings of the National Academy of Sciences of the United States of America
Komarov S
(2016)
Polarization of thermal bremsstrahlung emission due to electron pressure anisotropy
in Monthly Notices of the Royal Astronomical Society
Komarov S
(2016)
Thermal conduction in a mirror-unstable plasma
in Monthly Notices of the Royal Astronomical Society
Kozlowski PM
(2016)
Theory of Thomson scattering in inhomogeneous media.
in Scientific reports
Kuramitsu Y
(2016)
Model experiment of magnetic field amplification in laser-produced plasmas via the Richtmyer-Meshkov instability
in Physics of Plasmas
Kuramitsu Y
(2016)
Spherical shock in the presence of an external magnetic field
in Journal of Physics: Conference Series
Larder B
(2019)
Fast nonadiabatic dynamics of many-body quantum systems.
in Science advances
Li CK
(2016)
Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet.
in Nature communications
Mabey P
(2020)
Laboratory Study of Bilateral Supernova Remnants and Continuous MHD Shocks
in The Astrophysical Journal
Mabey P
(2019)
Laboratory study of stationary accretion shock relevant to astrophysical systems.
in Scientific reports
Mabey P
(2017)
A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics.
in Nature communications
Mallet A
(2016)
Measures of three-dimensional anisotropy and intermittency in strong Alfvénic turbulence
in Monthly Notices of the Royal Astronomical Society
McBride EE
(2018)
Setup for meV-resolution inelastic X-ray scattering measurements and X-ray diffraction at the Matter in Extreme Conditions endstation at the Linac Coherent Light Source.
in The Review of scientific instruments
Melville S
(2016)
Pressure-anisotropy-driven microturbulence and magnetic-field evolution in shearing, collisionless plasma
in Monthly Notices of the Royal Astronomical Society
Meyrand R
(2019)
Fluidization of collisionless plasma turbulence.
in Proceedings of the National Academy of Sciences of the United States of America
Michel T
(2018)
Analytical modelling of the expansion of a solid obstacle interacting with a radiative shock
in High Power Laser Science and Engineering
Miniati F
(2018)
Axion-Driven Cosmic Magnetogenesis during the QCD Crossover.
in Physical review letters
Moldabekov Z
(2022)
Towards a quantum fluid theory of correlated many-fermion systems from first principles
in SciPost Physics
Morita T
(2016)
Proton imaging of an electrostatic field structure formed in laser-produced counter-streaming plasmas
in Journal of Physics: Conference Series
Muller S
(2017)
Evolution of the Design and Fabrication of Astrophysics Targets for Turbulent Dynamo (TDYNO) Experiments on OMEGA
in Fusion Science and Technology
Oliver M
(2017)
Magneto-optic probe measurements in low density-supersonic jets
in Journal of Instrumentation
Palmer C
(2019)
Field reconstruction from proton radiography of intense laser driven magnetic reconnection
in Physics of Plasmas
Park H
(2016)
Laboratory astrophysical collisionless shock experiments on Omega and NIF
in Journal of Physics: Conference Series
Parker J
(2016)
Suppression of phase mixing in drift-kinetic plasma turbulence
in Physics of Plasmas
Perrone L
(2021)
Neutrino-electron magnetohydrodynamics in an expanding universe
in Physical Review D
Rigby A
(2018)
Electron acceleration by wave turbulence in a magnetized plasma
in Nature Physics
Rigby A
(2018)
Implementation of a Faraday rotation diagnostic at the OMEGA laser facility
in High Power Laser Science and Engineering
| Description | We have conducted a series of experiments at large laser facilities which show significant amplification of magnetic field in a turbulent plasma. This agrees with the expectation that turbulent dynamo is operative. Such conditions are believed to occur in the plasma found in cluster of galaxies. Our results thus provide an experimental confirmation of theoretical model of magnetogenesis during the formation of galaxies. Our results have been recently published in Nature Communications. In addition, we have developed advanced analytical techniques for quantitative proton radiography analysis. These techniques are important to the whole plasma/laser physics community. We have extended our experimental platform to study the amplification of magnetic fields in plasmas where compressibility effects become important. We have, first, worked on understanding the properties of compressible turbulence - results have appeared in Nature Communications - and then looked at how compressibility changes the onset of dynamo. We have published our results in PNAS. Finally, we have worked on understanding the effect of heat transport in magnetized plasmas - our results have appeared in Science Advances. |
| Exploitation Route | Experimental verification of turbulent dynamo has impacts in astrophysics, plasma physics and turbulence research. While this process has been predicted in numerical simulations, due to the limitations in computer resources, the quantitative details on how dynamo evolves are still unclear. Our work can thus provide a direct benchmark of the theory. |
| Sectors | Education,Energy |
| Description | Our results on magnetic field amplification by turbulence have been advertised to the general public. The most prominent activity we have undertaken was the Royal Society Summer of Science 2017 exhibit where some of our work has been presented at a level suitable for primary school students. |
| Sector | Education,Energy |
| Impact Types | Cultural |
| Description | Don Lamb |
| Organisation | University of Chicago |
| Department | Department of Astronomy and Astrophysics |
| Country | United States |
| Sector | Academic/University |
| PI Contribution | We provide the team in Chicago our expertise in the experimental diagnostics. |
| Collaborator Contribution | Don Lamb and his team provides us access to the FLASH code. Also, because of this collaboration, we can submit applications for laser time on the Omega laser facility |
| Impact | Astronomy, Plasma Physics, Lasers |
| Start Year | 2010 |
| Title | Software for "Building high accuracy emulators for scientific simulations with deep neural architecture search" |
| Description | This is the code and datasets for "Building high accuracy emulators for scientific simulations with deep neural architecture search". |
| Type Of Technology | Software |
| Year Produced | 2020 |
| Open Source License? | Yes |
| URL | https://zenodo.org/record/3782842 |
| Title | Software for "Building high accuracy emulators for scientific simulations with deep neural architecture search" |
| Description | This is the code and datasets for "Building high accuracy emulators for scientific simulations with deep neural architecture search". |
| Type Of Technology | Software |
| Year Produced | 2020 |
| Open Source License? | Yes |
| URL | https://zenodo.org/record/3782843 |