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This Letter reports the first complete observation of magnetized collisionless shock precursors formed through the compression of Biermann-battery magnetic fields in laser produced plasmas. At OMEGA, lasers produce a supersonic CH plasma flow which is magnetized with Biermann-battery magnetic fields. The plasma flow collides with an unmagnetized hydrogen gas jet plasma to create a magnetized shock precursor. The situation where the flowing plasma carries the magnetic field is similar to the Venusian bow shock. Imaging 2ω Thomson scattering confirms that the interaction is collisionless and shows density and temperature jumps. Proton radiographs have regions of strong deflections and FLASH magnetohydrodynamic (MHD) simulations show the presence of Biermann fields in the Thomson scattering region. Electrons are accelerated to energies of up to 100 keV in a power-law spectrum. OSIRIS particle-in-cell (PIC) simulations, initialized with measured parameters, show the formation of a magnetized shock precursor and corroborate the experimental observables.
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http://dx.doi.org/10.1103/PhysRevLett.134.125101 | DOI Listing |
Phys Rev Lett
July 2025
Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA.
We present the first collisionless realization of two-dimensional axisymmetric black hole accretion consistent with a persistent magnetically arrested disk state. The accretion flow, consisting of an ion-electron disk plasma combined with magnetospheric pair creation effects, is simulated using first-principles general-relativistic particle-in-cell methods. The simulation is evolved over significant dynamical timescales during which a quasisteady accretion state is reached with several magnetic flux eruption cycles.
View Article and Find Full Text PDFSpace Sci Rev
June 2025
Bison Aerospace, Inc., Newcastle, WY USA.
The detailed study of the global characteristics of collisionless magnetic reconnection that occurs at the magnetopause will be greatly enhanced by observations of plasma fluxes and fields within the low-altitude cusp region, as sampled by two spacecraft orbiting in tandem. The NASA Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) mission, a Heliophysics Small Explorer (SMEX) mission, will provide the necessary observations to enable significant progress to be made on understanding magnetic reconnection, especially in terms of its temporal versus spatial characteristics. This paper provides an overview of the TRACERS mission design and the trade studies conducted for the optimization of this design.
View Article and Find Full Text PDFPhys Rev E
April 2025
Tel Aviv University, School of Physics and Astronomy, Tel Aviv 69978, Israel.
In this paper, the first in a series, we present a new theoretical model for the global structure and dissipation of relativistically magnetized collisionless shock waves. Quite remarkably, we find that in contrast to unmagnetized shocks, the leading energy dissipation channel does not involve collective plasma interactions. Rather, it is a consequence of nonlinear particle dynamics.
View Article and Find Full Text PDFNat Commun
April 2025
State Key Laboratory of Ultra-intense Laser Science and Technology, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.
Relativistic collisionless shocks, which are ubiquitous in the cosmos, play a significant role in various astrophysical phenomena such as gamma-ray bursts, PeVatrons, and supernova shock breakouts. Here we present a demonstration using a compact femtosecond laser system to generate sub-relativistic collisionless shocks (0.03c) under astrophysically relevant conditions.
View Article and Find Full Text PDFPhys Rev Lett
March 2025
University of Bordeaux, Centre Lasers Intenses et Applications, CNRS, CEA, 33405 Talence, France.
This Letter reports the first complete observation of magnetized collisionless shock precursors formed through the compression of Biermann-battery magnetic fields in laser produced plasmas. At OMEGA, lasers produce a supersonic CH plasma flow which is magnetized with Biermann-battery magnetic fields. The plasma flow collides with an unmagnetized hydrogen gas jet plasma to create a magnetized shock precursor.
View Article and Find Full Text PDF