Evaporative cooling of antiprotons for the production of trappable antihydrogen

Journal Article · Tue Mar 19 00:00:00 EDT 2013 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4796072· OSTI ID:22113538

Silveira, D. M.; Cesar, C. L. ^[1]; Andresen, G. B.; Bowe, P. D.; Hangst, J. S. ^[2]; Ashkezari, M. D.; Hayden, M. E. ^[3]; Baquero-Ruiz, M.; Chapman, S.; Fajans, J.; Povilus, A.; So, C.; Wurtele, J. S. ^[4]; Bertsche, W. ^[5]; Butler, E. ^[6]; Charlton, M.; Madsen, N.; Werf, D. P. van der ^[7]; Friesen, T.; Hydomako, R. ^[8] ; others, and

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1. Instituto de Fisica - Universidade Federal do Rio de Janeiro, 21941-972, Rio de Janeiro (Brazil)
2. Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)
3. Department of Physics, Simon Fraser University, Burnaby BC, V5A 1S6 (Canada)
4. Department of Physics, University of California, Berkeley, California 94720-7300 (United States)
5. School of Physics and Astronomy, University of Manchester, M13 9PL Manchester (United Kingdom) and Cockroft Institute, WA4 4AD Warrington (United Kingdom)
6. CERN, PH Department, CH-1211 Geneva 23 (Switzerland)
7. Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom)
8. Department of Physics and Astronomy, University of Calgary AB, T2N 1N4 (Canada)

We describe the implementation of evaporative cooling of charged particles in the ALPHA apparatus. Forced evaporation has been applied to cold samples of antiprotons held in Malmberg-Penning traps. Temperatures on the order of 10 K were obtained, while retaining a significant fraction of the initial number of particles. We have developed a model for the evaporation process based on simple rate equations and applied it succesfully to the experimental data. We have also observed radial re-distribution of the clouds following evaporation, explained by simple conservation laws. We discuss the relevance of this technique for the recent demonstration of magnetic trapping of antihydrogen.

• OSTI ID: 22113538
• Journal Information: AIP Conference Proceedings, Vol. 1521, Issue 1; Conference: 10. international workshop on non-neutral plasmas, Greifswald (Germany), 27-30 Aug 2012; Other Information: (c) 2013 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ANTIPROTONS
ATOM COLLISIONS
CHARGED PARTICLES
CONSERVATION LAWS
EVAPORATIVE COOLING
HADRONIC ATOMS
MAGNETO-OPTICAL EFFECTS
PLASMA
REACTION KINETICS
TRAPPING
TRAPS