Laboratory for the Modelling of Plasma Phenomena in Extreme Astrophysical Objects

Scientific results:

The main results obtained by the Laboratory are related to interactions of powerful laser radiation with matter. The Laboratory possesses PEARL, the most powerful laser in Russia (up to 30 J, 910 ns, 10–50 fs), which is fully equipped for conducting laser-plasma experiments. Thanks to this, the Laboratory can conduct world-class experimental research in laser-assisted acceleration of charged particles and creating innovative terahertz, X-ray, gamma radiation, neutron sources on this basis that will have high peak brightness and distinguished by their compactness, low cost. and higher efficiency.
The applied significance of our research is related to the development of new principles for new principles for the creation of compact and bright sources for:

• phase-contrast X-ray microscope (the diagnostics of biological and other types of materials);
• problems of projection lithography;
• nuclear research and problems of neutron tomography, including fast processes and others.

The following world-class results have been achieved by the Laboratory:

1. Accelerating electron beams in the field of a wakefield plasma wave to energies at an order of magnitude of 1000 MeV.
2. Accelerating protons up to an energy of over 43,3 MeV when focusing a 200 TW laser pulse onto the surface of a thin aluminum target, which had for a long time been a world record for lasers with pulse energies not exceeding 20 J.
3. In collaboration with foreign organizations the authors of the project participated in the development of a laser-plasma source of neutrons with extremely short duration, as well as in demonstrating the peak characteristics of  TNSA acceleration of protons with  picosecond lasers and accelerating protons by a shock wave in supercritical gaseous targets.
4. We have created an experimental bench that allows to apply high-energy laser-plasma protons to biological objects. We demonstrated the capability of laser-plasma protons to impart a dose of up to 10 Gray to the research object in a single shot.
5. A methodology has been developed for irradiating a HeLa Kyoto cell culture and measuring the fraction of surviving cells.
6. Methods have been developed for modeling processes of the formation of young stars in a laboratory setting, which allows to complement astrophysical observations with laboratory measurements and obtain new data on the physical processes in young stars.
7. A new experimental approach has been proposed that allows to research the interaction of supersonic (ionic Mach number up to 2.7) plasma flows with high density (concentration of up to 10¹⁵ cm⁻³) and an inhomogeneous magnetic field.
8. The Laboratory has proposed a model of collisionless relativistic shock waves, that allows to describe the acceleration of particles, their radiation as well as the generation and attenuation of a magnetic field in a self-consistent manner. The scope of applicability of the model includes gamma splashes and the active cores of galaxies.
9. We have conducted experimental and numerical research of the processes of interaction of high-speed dense plasma flows with a solid target in an external magnetic field to model the physical processes developing in the bases of accretion columns during the magnetospheric accretion of matter onto young stars.
10. The Laboratory has researched the mechanisms of the formation of collimated plasma structures due to radiation self-channeling  in self-sustaining plasma waveguides with lowered plasma density. It was demonstrated that, the self-channeling of the propagation of Langmuir waves is possible in such plasma waveguides, which can serve as the basis for building new models of astrophysical jets.
11. Our researchers have conducted a laboratory study of the processes of interaction of dense plasma flows with a transverse external magnetic field. The main astrophysical problems related to such interaction, the accretion of matter onto compact stars possessing their own magnetic fields and flare processes on the Sun and other stars. The principal attention was paid to the processes developing in the region where the pressure of the magnetic field is of the same order of magnitude as the gas dynamic pressure of the plasma flow. Using two interferometers, we obtained instant two-dimensional images of the spatial distribution of plasma on the time interval from 0 to 100 ns after the beginning of the formation of a plasma cloud in two planes: perpendicular and parallel to the force lines of the magnetic field It was demonstrated that as a result of the interaction of the plasma flow with an external magnetic field directed orthogonally to the direction of the dispersion of plasma, a thin plasma layer is formed that propagates across long distances into the volume occupied by the magnetic field (the thin plasma layer penetrates between the force lines of the magnetic field). This result, which has been confirmed by numerical modeling as well, calls into question the model of the falling of matter from an accretion disc onto a star along the lines of the magnetic field that is generally accepted in astrophysics (i. e. matter falling onto the magnetic poles) and allows to propose an alternate model  of the falling of matter onto the equator.

Implemented results of research: 

• We have developed an original pulse magnetic system that is cooled with liquid nitrogen with a maximum magnetic field inductance of up to 20Т. The system is used to conduct a wide range of research in laser-plasma interaction and laboratory astrophysics.
• A technology has been developed that allows for a multiple increase in the peak intensity of focused ultra-high-power femtosecond laser radiation that is based on the nonlinear postcompression of a laser pulse with subsequent compensation of arising nonlinear distortions of the wave front using  a deformable mirror.

• We have organized internships for young researchers and students at international organizations: École polytechnique (France), the Lawrence Livermore National Laboratory (USA), the Helmholtz Center for Heavy Ion Research (Germany), the French National Center for Scientific Research (France).

• One Doctor of Sciences dissertations and two Candidate of Sciences dissertations have been prepared and defended.

• We have implemented a special course for master’s degree and postgraduate students majoring in Radiophysics.

• We have implemented the special course «High-power laser systems».

• Our team have established scientific collaborations in the domain of laboratory astrophysics with Russian institutes and at the international level.

• The Laboratory conducted the thematic international conference  LaB–2017.

• We have created PEARL, the first interdisciplinary laser-plasma experimental complex in Russia that operates at the petawatt level and allows to implement unique experimental parameters using several types of laser radiation and a system for creating strong external magnetic fields.
• The Laboratory conducted schools for young researchers devoted to problems of the interaction of ultra-strong laser radiation and matter (2021–2022). 

Collaborations:

• École polytechnique (France), 
• Lawrence Livermore National Laboratory (USA), 
• Helmholtz Center for Heavy Ion Research (Germany), 
• French National Center for Scientific Research (France), 
• Joint Institute for High Temperatures of the Russian Academy of Sciences, 
• Lebedev Physical Institute of the Russian Academy of Sciences, 
• Moscow Engineering Physics Institute, 
• Russian Federal Nuclear Center – All-Russian Scientific Research Institute of Experimental Physics: joint research, conducting collaborative experiments in laser-plasma interactions and acceleration of charged particles (more than 50 articles have been published in collaboration with employees of said organizations).