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arXiv · 2201.08595

Confinement of relativistic electrons in a magnetic mirror en route to a magnetized relativistic pair plasma

J. von der Linden·G. Fiksel·J. Peebles·M. R. Edwards·L. Willingale·A. Link·D. Mastrosimone·Hui Chen
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Abstract

Creating 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 towards a laboratory pair plasma, we have demonstrated effective confinement of multi-$\mathrm{MeV}$ electrons inside a pulsed-power-driven $13$ $\mathrm{T}$ 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 $\leq 2.5$ $\mathrm{MeV}$ electrons confined in the mirror for $\sim 1$ $\mathrm{ns}$. With a source of $10^{12}$ electron-positron pairs at comparable energies, this magnetic mirror would confine a relativistic pair plasma with Lorentz factor $\gamma \sim 6$ and magnetization $\sigma \sim 40$.

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J. von der Linden, G. Fiksel, J. Peebles, M. R. Edwards, L. Willingale, A. Link, D. Mastrosimone, Hui Chen. 2022-01-21. Confinement of relativistic electrons in a magnetic mirror en route to a magnetized relativistic pair plasma. https://doi.org/10.1063/5.0057582

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