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AEGIS at CERN: Measuring Antihydrogen Fall  [PDF]
Marco G. Giammarchi
Physics , 2011, DOI: 10.1007/s00601-012-0439-6
Abstract: The main goal of the AEGIS experiment at the CERN Antiproton Decelerator is the test of fundamental laws such as the Weak Equivalence Principle (WEP) and CPT symmetry. In the first phase of AEGIS, a beam of antihydrogen will be formed whose fall in the gravitational field is measured in a Moire' deflectometer; this will constitute the first test of the WEP with antimatter.
First Production and Detection of Cold Antihydrogen Atoms  [PDF]
M. C. Fujiwara,M. Amoretti,C. Amsler,G. Bonomi,A. Bouchta,P. Bowe,C. Carraro,C. L. Cesar,M. Charlton,M. Doser,V. Filippini,A. Fontana,R. Funakoshi,P. Genova,J. S. Hangst,R. S. Hayano,L. V. Jorgensen,V. Lagomarsino,R. Landua,D. Lindelof,E. Lodi Rizzini,M. Marchesotti,M. Macri,N. Madsen,P. Montagna,H. Pruys,C. Regenfus,P. Rielder,A. Rotondi,G. Testera,A. Variola,D. P. van der Werf
Physics , 2003, DOI: 10.1016/S0168-583X(03)01775-0
Abstract: The ATHENA experiment recently produced the first atoms of cold antihydrogen. This paper gives a brief review of how this was achieved.
Measurement of the hyperfine structure of antihydrogen in a beam  [PDF]
E. Widmann,M. Diermaier,B. Juhasz,C. Malbrunot,O. Massiczek,C. Sauerzopf,K. Suzuki,B. Wünschek,J. Zmeskal,S. Federmann,N. Kuroda,S. Ulmer,Y. Yamazaki
Physics , 2013, DOI: 10.1007/s10751-013-0809-6
Abstract: A measurement of the hyperfine structure of antihydrogen promises one of the best tests of CPT symmetry. We describe an experiment planned at the Antiproton Decelerator of CERN to measure this quantity in a beam of slow antihydrogen atoms.
Prospects for measuring the gravitational free-fall of antihydrogen with emulsion detectors  [PDF]
AEgIS Collaboration,S. Aghion,O. Ahlén,C. Amsler,A. Ariga,T. Ariga,A. S. Belov,G. Bonomi,P. Br?unig,J. Bremer,R. S. Brusa,L. Cabaret,C. Canali,R. Caravita,F. Castelli,G. Cerchiari,S. Cialdi,D. Comparat,G. Consolati,J. H. Derking,S. Di Domizio,L. Di Noto,M. Doser,A. Dudarev,A. Ereditato,R. Ferragut,A. Fontana,P. Genova,M. Giammarchi,A. Gligorova,S. N. Gninenko,S. Haider,J. Harasimovicz,S. D. Hogan,T. Huse,E. Jordan,L. V. J?rgensen,T. Kaltenbacher,J. Kawada,A. Kellerbauer,M. Kimura,A. Knecht,D. Krasnicky,V. Lagomarsino,A. Magnani,S. Mariazzi,V. A. Matveev,F. Moia,G. Nebbia,P. Nédélec,M. K. Oberthaler,N. Pacifico,V. Petrácek,C. Pistillo,F. Prelz,M. Prevedelli,C. Regenfus,C. Riccardi,O. R?hne,A. Rotondi,H. Sandaker,P. Scampoli,A. Sosa,J. Storey,M. A. Subieta Vasquez,M. Spacek,G. Testera,D. Trezzi,R. Vaccarone,C. P. Welsch,S. Zavatarelli
Physics , 2013, DOI: 10.1088/1748-0221/8/08/P08013
Abstract: The main goal of the AEgIS experiment at CERN is to test the weak equivalence principle for antimatter. AEgIS will measure the free-fall of an antihydrogen beam traversing a moir\'e deflectometer. The goal is to determine the gravitational acceleration g for antihydrogen with an initial relative accuracy of 1% by using an emulsion detector combined with a silicon micro-strip detector to measure the time of flight. Nuclear emulsions can measure the annihilation vertex of antihydrogen atoms with a precision of about 1 - 2 microns r.m.s. We present here results for emulsion detectors operated in vacuum using low energy antiprotons from the CERN antiproton decelerator. We compare with Monte Carlo simulations, and discuss the impact on the AEgIS project.
The First Cold Antihydrogen  [PDF]
M. C. Fujiwara,M. Amoretti,C. Amsler,G. Bonomi,A. Bouchta,P. D. Bowe,C. Carraro,C. L. Cesar,M. Charlton,M. Doser,V. Filippini,A. Fontana,R. Funakoshi,P. Genova,J. S. Hangst,R. S. Hayano,L. V. Jorgensen,V. Lagomarsino,R. Landua,D. Lindelof,E. Lodi Rizzini,M. Macri,N. Madsen,M. Marchesotti,P. Montagna,H. Pruys,C. Regenfus,P. Rielder,A. Rotondi,G. Testera,A. Variola,D. P. van der Werf
Physics , 2004, DOI: 10.1016/j.nima.2004.06.050
Abstract: Antihydrogen, the atomic bound state of an antiproton and a positron, was produced at low energy for the first time by the ATHENA experiment, marking an important first step for precision studies of atomic antimatter. This paper describes the first production and some subsequent developments.
ATHENA -- First Production of Cold Antihydrogen and Beyond  [PDF]
ATHENA Collaboration,A. Kellerbauer,M. Amoretti,C. Amsler,G. Bonomi,P. D. Bowe,C. Canali,C. Carraro,C. L. Cesar,M. Charlton,M. Doser,A. Fontana,M. C. Fujiwara,R. Funakoshi,P. Genova,J. S. Hangst,R. S. Hayano,I. Johnson,L. V. J?rgensen,V. Lagomarsino,R. Landua,E. Lodi Rizzini,M. Macrí,N. Madsen,G. Manuzio,D. Mitchard,P. Montagna,H. Pruys,C. Regenfus,A. Rotondi,G. Testera,A. Variola,L. Venturelli,D. P. van der Werf,Y. Yamazaki,N. Zurlo
Physics , 2004,
Abstract: Atomic systems of antiparticles are the laboratories of choice for tests of CPT symmetry with antimatter. The ATHENA experiment was the first to report the production of copious amounts of cold antihydrogen in 2002. This article reviews some of the insights that have since been gained concerning the antihydrogen production process as well as the external and internal properties of the produced anti-atoms. Furthermore, the implications of those results on future prospects of symmetry tests with antimatter are discussed.
Antihydrogen  [PDF]
Ivan Schmidt
Physics , 1997, DOI: 10.1063/1.53213
Abstract: CERN announced in January 1996 the detection of the first eleven atoms of antimatter ever produced. The experiment was based on a method proposed earlier by S. Brodsky, C. Munger and I. Schmidt, and which furthermore predicted exactly the number of atoms that were detected for the particular conditions of the experiment. The study of antihydrogen affords science the opportunity to continue research on the symmetry between matter and antimatter. In this talk the importance of antihydrogen as a basic physical system is discussed. Different production methods that have been tried in the past are briefly presented, and the method that was used in the CERN experiment is analyzed in detail. It consists in producing antihydrogen by circulating a beam of an antiproton ring through an internal gas target. In the Coulomb field of a nucleus, an electron-positron pair is created, and antihydrogen will form when the positron is created in a bound rather that a continuum state about the antiproton. The theoretical calculation of the production cross section is presented in detail. A discussion of the detection systems used both in the CERN experiment and in another similar experiment that is right now underway at Fermilab are also given. Finally I present and discuss possible future experiments using antihydrogen, including the measurement of the antihydrogen Lamb shift.
Production of Cold Antihydrogen with ATHENA for Fundamental Studies  [PDF]
ATHENA Collaboration,A. Kellerbauer,M. Amoretti,C. Amsler,G. Bonomi,P. D. Bowe,C. Canali,C. Carraro,C. L. Cesar,M. Charlton,M. Doser,A. Fontana,M. C. Fujiwara,R. Funakoshi,P. Genova,J. S. Hangst,R. S. Hayano,I. Johnson,L. V. J?rgensen,V. Lagomarsino,R. Landua,E. Lodi Rizzini,M. Macrí,N. Madsen,G. Manuzio,D. Mitchard,P. Montagna,H. Pruys,C. Regenfus,A. Rotondi,G. Testera,A. Variola,L. Venturelli,D. P. van der Werf,Y. Yamazaki,N. Zurlo
Physics , 2004,
Abstract: Since the beginning of operations of the CERN Antiproton Decelerator in July 2000, the successful deceleration, storage and manipulation of antiprotons has led to remarkable progress in the production of antimatter. The ATHENA Collaboration were the first to create and detect cold antihydrogen in 2002, and we can today produce large enough amounts of antiatoms to study their properties as well as the parameters that govern their production rate.
Prospects for Forbidden-Transition Spectroscopy and Parity Violation Measurements using a Beam of Cold Stable or Radioactive Atoms  [PDF]
S. Sanguinetti,J. Guéna,M. Lintz,Ph. Jacquier,A. Wasan,M-A. Bouchiat
Physics , 2003, DOI: 10.1140/epjd/e2003-00215-5
Abstract: Laser cooling and trapping offers the possibility of confining a sample of radioactive atoms in free space. Here, we address the question of how best to take advantage of cold atom properties to perform the observation of as highly forbidden a line as the 6S-7S Cs transition for achieving, in the longer term, Atomic Parity Violation measurements in radioactive alkali isotopes. Another point at issue is whether one might do better with stable, cold atoms than with thermal atoms. To compensate for the large drawback of the small number of atoms available in a trap, one must take advantage of their low velocity. To lengthen the time of interaction with the excitation laser, we suggest choosing a geometry where the laser beam exciting the transition is colinear to a slow, cold atomic beam, either extracted from a trap or prepared by Zeeman slowing. We also suggest a new observable physical quantity manifesting APV, which presents several advantages:specificity, efficiency of detection, possibility of direct calibration by a parity conserving quantity of a similar nature. It is well adapted to a configuration where the cold atomic beam passes through two regions of transverse, crossed electric fields, leading both to differential measurements and to strong reduction of the contributions from the M_1-Stark interference signals, potential sources of systematics in APV measurements. Our evaluation of signal to noise ratios shows that with available techniques, measurements of transition amplitudes, important as required tests of Atomic Theory should be possible in cesium 133 with a statistical precision of 1/1000 and probably also in Fr isotopes for production rates of 10^6 Fr atoms/s.
Nonlinear dynamics of antihydrogen in magnetostatic traps: implications for gravitational measurements  [PDF]
Andrey Zhmoginov,Andrew Charman,Joel Fajans,Jonathan Wurtele
Physics , 2013, DOI: 10.1088/0264-9381/30/20/205014
Abstract: The influence of gravity on antihydrogen dynamics in magnetic traps is studied. The advantages and disadvantages of various techniques for measuring the ratio of the gravitational mass to the inertial mass of antihydrogen are discussed. Theoretical considerations and numerical simulations indicate that stochasticity may be especially important for some experimental techniques in vertically oriented traps.
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