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  • Letter
  • Open Access

Positron transport and cooling with CF4 in an inhomogeneous magnetic field

J. von der Linden1,*,†, A. Deller1,2, S. Nißl1, K. Michishio3, H. Higaki4, and E. V. Stenson1

  • *Present address: Thea Energy, Inc., Kearny, New Jersey 07032, USA.
  • †Contact author: jens.vonderlinden@thea.energy
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Phys. Rev. Research 8, L032002 – Published 6 July, 2026

DOI: https://doi.org/10.1103/dvwc-y28s

Abstract

We present measurements of positrons (e+) undergoing transport and cooling with molecular CF4 in the inhomogeneous magnetic field of a dipole trap. The annihilation rate and γ-ray spectra reveal a shift in the primary loss channel from positronium (Ps) formation to collisional cross-field transport. This transition is mediated by molecules cooling e+ below the charge-exchange threshold for Ps formation. Elucidating the interplay between cooling and annihilation is crucial for optimizing e+ confinement schemes and refining models of astrophysical γ-ray spectra.

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Phys. Rev. Research 8, L032002– Published 6 July, 2026
  • Received 1 November 2025
  • Revised 25 January 2026
  • Accepted 10 June 2026
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