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Abstract We present a phenomenological and numerical study of strong Alfvénic turbulence in a magnetically dominated collisionless relativistic plasma with a strong background magnetic field. In contrast with the nonrelativistic case, the energy in such turbulence is contained in magnetic and electric fluctuations. We argue that such turbulence is analogous to turbulence in a strongly magnetized nonrelativistic plasma in the regime of broken quasi-neutrality. Our 2D particle-in-cell numerical simulations of turbulence in a relativistic pair plasma find that the spectrum of the total energy has the scalingk−3/2, while the difference between the magnetic and electric energies, the so-called residual energy, has the scalingk−2.4. The electric and magnetic fluctuations at scaleℓexhibit dynamic alignment with the alignment angle scaling close to . At scales smaller than the (relativistic) plasma inertial scale, the energy spectrum of relativistic inertial Alfvén turbulence steepens tok−3.5.
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Confinement of relativistic electrons in a magnetic mirror en route to a magnetized relativistic pair plasma
Creating a magnetized relativistic pair plasma in the laboratory would enable the exploration of unique plasma physics relevant to some of the most energetic events in the universe. As a step toward a laboratory pair plasma, we have demonstrated an effective confinement of multi-MeV electrons inside a pulsed-power-driven 13 T magnetic mirror field with a mirror ratio of 2.6. The confinement is diagnosed by measuring the axial and radial losses with magnetic spectrometers. The loss spectra are consistent with ≤2.5 MeV electrons confined in the mirror for ∼1 ns. With a source of 1012 electron-positron pairs at comparable energies, this magnetic mirror would confine a relativistic pair plasma with Lorentz factor γ∼6 and magnetization σ∼40.
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- Award ID(s):
- 1751462
- PAR ID:
- 10591884
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Physics of Plasmas
- Volume:
- 28
- Issue:
- 9
- ISSN:
- 1070-664X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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