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arXiv · 1104.4841

Centrifugal separation and equilibration dynamics in an electron-antiproton plasma

G. B. Andresen·M. D. Ashkezari·M. Baquero-Ruiz·W. Bertsche·P. D. Bowe·E. Butler·C. L. Cesar·S. Chapman·M. Charlton·A. Deller·S. Eriksson·J. Fajans·T. Friesen·M. C. Fujiwara·D. R. Gill·A. Gutierrez·J. S. Hangst·W. N. Hardy·M. E. Hayden·A. J. Humphries·R. Hydomako·S. Jonsell·N. Madsen·S. Menary·P. Nolan·A. Olin·A. Povilus·P. Pusa·F. Robicheaux·E. Sarid·D. M. Silveira·C. So·J. W. Storey·R. I. Thompson·D. P. van der Werf·J. S. Wurtele·Y. Yamazaki
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Abstract

Charges in cold, multiple-species, non-neutral plasmas separate radially by mass, forming centrifugally-separated states. Here, we report the first detailed measurements of such states in an electron-antiproton plasma, and the first observations of the separation dynamics in any centrifugally-separated system. While the observed equilibrium states are expected and in agreement with theory, the equilibration time is approximately constant over a wide range of parameters, a surprising and as yet unexplained result. Electron-antiproton plasmas play a crucial role in antihydrogen trapping experiments.

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G. B. Andresen, M. D. Ashkezari, M. Baquero-Ruiz, W. Bertsche, P. D. Bowe, E. Butler, C. L. Cesar, S. Chapman, M. Charlton, A. Deller, S. Eriksson, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, A. Gutierrez, J. S. Hangst, W. N. Hardy, M. E. Hayden, A. J. Humphries, R. Hydomako, S. Jonsell, N. Madsen, S. Menary, P. Nolan, A. Olin, A. Povilus, P. Pusa, F. Robicheaux, E. Sarid, D. M. Silveira, C. So, J. W. Storey, R. I. Thompson, D. P. van der Werf, J. S. Wurtele, Y. Yamazaki. 2011-04-26. Centrifugal separation and equilibration dynamics in an electron-antiproton plasma. https://doi.org/10.1103/physrevlett.106.145001

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