Speaker
Description
Buffer-gas positron traps (BGT) are invaluable for high-resolution matter-antimatter interaction studies, antihydrogen research, and positronium laser spectroscopy. These devices exploit inelastic interactions between positrons and nitrogen molecules to accrue a nonneutral $e^+$ plasma [1]. We present plans to produce short pulses of very low-energy positrons by installing a BGT at the NEPOMUC positron facility [2].
A two-stage BGT and accumulator has been constructed at MPG-IPP to capture positrons from the 20-eV, remoderated NEPOMUC positron beam [3]. Testing of the traps with electron plasmas is underway. Potential applications for the NEPOMUC BGT include positron-annihilation-induced Auger-electron spectroscopy and production of a very dense positronium gas. Together with a high-field multicell trap [4], the BGT will be a crucial component of the APEX pair-plasma experiment [5], which requires an unprecedented number of low-energy positrons.
This work supported by European Research Council (ERC-2016-ADG No. 741322), U.S. DOE (DE-SC0019271), and the UCSD Foundation.
[1] Murphy, et al., Phys. Rev. A 46, 5696 (1992).
[2] Hugenschmidt, et al., New J. Phys. 14 055027 (2012)
[3] Stanja, et al., Nuc. Inst. Methods A 827, 52 (2016).
[4] Singer, et al., Rev. Sci. Inst. 92, 123504 (2021).
[5] Stoneking, et al., J. Plasma Phys. 86, 15586061 (2020).
