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Confinement of antihydrogen for 1,000 seconds

Nature Physics volume 7, pages 558–564 (2011)Cite this article

Abstract

Atoms made of a particle and an antiparticle are unstable, usually surviving less than a microsecond. Antihydrogen, made entirely of antiparticles, is believed to be stable, and it is this longevity that holds the promise of precision studies of matter–antimatter symmetry. We have recently demonstrated trapping of antihydrogen atoms by releasing them after a confinement time of 172 ms. A critical question for future studies is: how long can anti-atoms be trapped? Here, we report the observation of anti-atom confinement for 1,000 s, extending our earlier results by nearly four orders of magnitude. Our calculations indicate that most of the trapped anti-atoms reach the ground state. Further, we report the first measurement of the energy distribution of trapped antihydrogen, which, coupled with detailed comparisons with simulations, provides a key tool for the systematic investigation of trapping dynamics. These advances open up a range of experimental possibilities, including precision studies of charge–parity–time reversal symmetry and cooling to temperatures where gravitational effects could become apparent.

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Figure 1: The ALPHA antihydrogen trap and its magnetic-field configuration.
Figure 2: Long-time confinement of antihydrogen.
Figure 3: Antihydrogen annihilation patterns and comparisons with simulations.
Figure 4: Dynamics of trapped antihydrogen from the standard simulation.

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Acknowledgements

This work was supported in part by CNPq, FINEP/RENAFAE (Brazil), NSERC, NRC/TRIUMF, AIF, FQRNT (Canada), FNU (Denmark), ISF (Israel), MEXT (Japan), VR (Sweden), EPSRC, the Royal Society and the Leverhulme Trust (UK) and DOE, NSF (USA). We are grateful to the AD team for the delivery of a high-quality antiproton beam.

Author information

Author notes

  1. S. L. Kemp

    Present address: Present address: Department of Physics, Durham University, Durham DH1 3LE, UK,

  2. J. W. Storey

    Present address: Present address: Physik-Institut, Zürich University, CH-8057 Zürich, Switzerland,

Authors and Affiliations

  1. Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark

    G. B. Andresen, P. D. Bowe, J. S. Hangst & C. Ø. Rasmussen

  2. Department of Physics, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada

    M. D. Ashkezari & M. E. Hayden

  3. Department of Physics, University of California, Berkeley, California 94720-7300, USA

    M. Baquero-Ruiz, J. Fajans, C. So & J. S. Wurtele

  4. Department of Physics, Swansea University, Swansea SA2 8PP, UK

    W. Bertsche, M. Charlton, A. Deller, S. Eriksson, A. J. Humphries, N. Madsen & D. P. van der Werf

  5. Physics Department, CERN, CH-1211 Geneva 23, Switzerland

    E. Butler & S. L. Kemp

  6. Instituto de Fısica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-972, Brazil

    C. L. Cesar

  7. Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA

    J. Fajans & J. S. Wurtele

  8. Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, T2N 1N4, Canada

    T. Friesen, M. C. Fujiwara, R. Hydomako & R. I. Thompson

  9. TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3, Canada

    M. C. Fujiwara, D. R. Gill, L. Kurchaninov, K. Olchanski, A. Olin & J. W. Storey

  10. Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, V6T 1Z1, Canada

    A. Gutierrez & W. N. Hardy

  11. Department of Physics, University of Tokyo, Tokyo 113-0033, Japan

    R. S. Hayano

  12. Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden

    S. Jonsell

  13. Department of Physics and Astronomy, York University, Toronto, Ontario, M3J 1P3, Canada

    S. Menary

  14. Department of Physics, University of Liverpool, Liverpool L69 7ZE, UK

    P. Nolan & P. Pusa

  15. Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, V8P 5C2, Canada

    A. Olin

  16. Department of Physics, Auburn University, Auburn, Alabama 36849-5311, USA

    F. Robicheaux

  17. Department of Physics, NRCN-Nuclear Research Center Negev, Beer Sheva, IL-84190, Israel

    E. Sarid

  18. Atomic Physics Laboratory, RIKEN, Saitama 351-0198, Japan

    D. M. Silveira & Y. Yamazaki

  19. Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan

    Y. Yamazaki

Consortia

The ALPHA Collaboration

  • G. B. Andresen
  • , M. D. Ashkezari
  • , M. Baquero-Ruiz
  • , W. Bertsche
  • , P. D. Bowe
  • , E. Butler
  • , C. L. Cesar
  • , M. Charlton
  • , A. Deller
  • , S. Eriksson
  • , J. Fajans
  • , T. Friesen
  • , M. C. Fujiwara
  • , D. R. Gill
  • , A. Gutierrez
  • , J. S. Hangst
  • , W. N. Hardy
  • , R. S. Hayano
  • , M. E. Hayden
  • , A. J. Humphries
  • , R. Hydomako
  • , S. Jonsell
  • , S. L. Kemp
  • , L. Kurchaninov
  • , N. Madsen
  • , S. Menary
  • , P. Nolan
  • , K. Olchanski
  • , A. Olin
  • , P. Pusa
  • , C. Ø. Rasmussen
  • , 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

Contributions

All authors contributed significantly to this work.

Corresponding authors

Correspondence to M. C. Fujiwara or J. S. Hangst.

Ethics declarations

Competing interests

The author declare no competing financial interests.

Additional information

A full list of authors appears at the end of this paper.

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The ALPHA Collaboration. Confinement of antihydrogen for 1,000 seconds. Nature Phys 7, 558–564 (2011). https://doi.org/10.1038/nphys2025

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