Trapped antihydrogen

  title={Trapped antihydrogen},
  author={Gorm Bruun Andresen and Mohammad D. Ashkezari and M. Baquero-Ruiz and W. A. Bertsche and Paul D. Bowe and E Butler and C. L. Cesar and Scott Chapman and M Charlton and A. Deller and Stefan Eriksson and Joel Fajans and Timothy P. Friesen and M C Fujiwara and David Russell Gill and Andrea Gutierrez and Jeffrey S. Hangst and W. N. Hardy and Michael Edward Hayden and Andrew J. Humphries and Richard Hydomako and Michael J. Jenkins and Svante Jonsell and Lars V. J{\o}rgensen and Lenoid Kurchaninov and N Madsen and Scott Robert Menary and Paul J. Nolan and Konstantin Olchanski and A Olin and Alexander Povilus and Petteri Pusa and Francis Robicheaux and Eli Sarid and Sarah Seif El Nasr and Daniel Miranda Silveira and Chukman So and John W. V. Storey and R Ichard L. Thompson and D. P. Werf and Jonathan S. Wurtele and Yasunori Yamazaki},
Antimatter was first predicted in 1931, by Dirac. Work with high-energy antiparticles is now commonplace, and anti-electrons are used regularly in the medical technique of positron emission tomography scanning. Antihydrogen, the bound state of an antiproton and a positron, has been produced at low energies at CERN (the European Organization for Nuclear Research) since 2002. Antihydrogen is of interest for use in a precision test of nature’s fundamental symmetries. The charge conjugation/parity… 
Testing CPT And Antigravity With Trapped Antihydrogen At ALPHA
High precision antihydrogen experiments allow tests of fundamental theoretical descriptions of nature. These experiments are performed with the ALPHA apparatus, where ultra-low energy antihydrogen is
Antihydrogen accumulation for fundamental symmetry tests
An efficient and high-precision method for trapping and stacking antihydrogen by using controlled plasma is demonstrated, with a record of 54 detected annihilation events from a single release of the trapped anti-atoms accumulated from five consecutive cycles.
Characterization of the 1S–2S transition in antihydrogen
The shape of the spectral line and the resonance frequency of the 1S–2S transition in antihydrogen agree very well with those of hydrogen, consistent with charge–parity–time invariance at a relative precision of 2 × 10−12—two orders of magnitude more precise than the previous determination.
Quantum suppression of antihydrogen formation in positronium-antiproton scattering
The authors have predicted the quantum suppression of the cross-section for antihydrogen formation in positronium scattering with antiprotons, by including the excited states and using convergent close-coupling calculations.
Antihydrogen studies in ALPHA
The ALPHA experiment studies antihydrogen as a means to investigate the symmetry of matter and antimatter. Spectroscopic studies of the anti-atom hold the promise of the most precise direct
Observation of the hyperfine spectrum of antihydrogen
The results of a microwave spectroscopy experiment in which the response of antihydrogen is probed over a controlled range of frequencies reveal clear and distinct signatures of two allowed transitions, from which a direct, magnetic-field-independent measurement of the hyperfine splitting is obtained.
Laser-Ablated Beryllium Ions for Cold Antihydrogen in ALPHA
One of the best ways to study antimatter is to investigate antihydrogen, the bound state of an antiproton and a positron. Antihydrogen atoms do not exist naturally and must be synthesized in the lab
In-beam measurement of the hydrogen hyperfine splitting and prospects for antihydrogen spectroscopy
A measurement of the zero-field hydrogen GS-HFS is presented using the spectroscopy apparatus of ASACUSA's antihydrogen experiment and proves the most precise determination of this quantity in a beam and verifies the developed spectroscopic methods for the antihydrogens HFS experiment to the p.p.b. level.
A source of antihydrogen for in-flight hyperfine spectroscopy
This work reports the development of an antihydrogen source using a cusp trap for in-flight spectroscopy, a major step towards precision spectroscopic of the ground-state hyperfine splitting of antiHydrogen using Rabi-like beam spectroscope.
Cold and stable antimatter for fundamental physics
  • Y. Yamazaki
  • Medicine
    Proceedings of the Japan Academy. Series B, Physical and biological sciences
  • 2020
The field of cold antimatter physics has rapidly developed in the last 20 years, overlapping with the period of the Antiproton Decelerator (AD) at CERN. The central subjects are CPT symmetry tests


Production and detection of cold antihydrogen atoms
This work demonstrates the production of antihydrogen atoms at very low energy by mixing trapped antiprotons and positrons in a cryogenic environment and detects the neutral anti-atoms directly when they escape the trap and annihilate, producing a characteristic signature in an imaging particle detector.
Search For Trapped Antihydrogen
Abstract We present the results of an experiment to search for trapped antihydrogen atoms with the ALPHA antihydrogen trap at the CERN Antiproton Decelerator. Sensitive diagnostics of the
Emerging science and technology of antimatter plasmas and trap-based beams
Progress in the ability to accumulate and cool positrons and antiprotons is enabling new scientific and technological opportunities. The driver for this work is plasma physics research—developing new
A magnetic trap for antihydrogen confinement
The goal of the ALPHA collaboration at CERN is to test CPT conservation by comparing the 1S–2S transitions of hydrogen and antihydrogen. To reach the ultimate accuracy of 1 part in 10 18 , the
Antihydrogen formation dynamics in a multipolar neutral anti-atom trap
Abstract Antihydrogen production in a neutral atom trap formed by an octupole-based magnetic field minimum is demonstrated using field-ionization of weakly bound anti-atoms. Using our unique
Particle Physics Aspects of Antihydrogen Studies with ALPHA at CERN
We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERN's Antiproton Decelerator facility. We review the
Antimatter plasmas in a multipole trap for antihydrogen.
The storage lifetimes of antiproton and positron plasmas in the combined Penning-neutral trap are measured, and compared to lifetimes without the neutral trap fields.
First capture of antiprotons in a Penning trap: A kiloelectronvolt source.
Prospects are now excellent for much longer trapping times under better vacuum conditions, and the feasibility of a greatly improved measurement of the inertial mass of the antiproton is demonstrated.
Antihydrogen production temperature dependence
Cold antihydrogen atoms were produced by mixing cold samples of antiprotons and positrons. The temperature of the positron plasma was increased by controlled radio-frequency (RF) heating, and the
Antihydrogen production using trapped plasmas
Abstract Now that antiprotons have been captured in an ion trap, we investigate the possibility of producing antihydrogen by merging cold trapped plasmas of antiprotons and positrons. The calculated