The First Cold Antihydrogen*
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Interactions of Antiprotons with Atoms and Molecules
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln US Department of Energy Publications U.S. Department of Energy 1988 INTERACTIONS OF ANTIPROTONS WITH ATOMS AND MOLECULES Mitio Inokuti Argonne National Laboratory Follow this and additional works at: https://digitalcommons.unl.edu/usdoepub Part of the Bioresource and Agricultural Engineering Commons Inokuti, Mitio, "INTERACTIONS OF ANTIPROTONS WITH ATOMS AND MOLECULES" (1988). US Department of Energy Publications. 89. https://digitalcommons.unl.edu/usdoepub/89 This Article is brought to you for free and open access by the U.S. Department of Energy at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in US Department of Energy Publications by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. /'Iud Tracks Radial. Meas., Vol. 16, No. 2/3, pp. 115-123, 1989 0735-245X/89 $3.00 + 0.00 Inl. J. Radial. Appl .. Ins/rum., Part D Pergamon Press pic printed in Great Bntam INTERACTIONS OF ANTIPROTONS WITH ATOMS AND MOLECULES* Mmo INOKUTI Argonne National Laboratory, Argonne, Illinois 60439, U.S.A. (Received 14 November 1988) Abstract-Antiproton beams of relatively low energies (below hundreds of MeV) have recently become available. The present article discusses the significance of those beams in the contexts of radiation physics and of atomic and molecular physics. Studies on individual collisions of antiprotons with atoms and molecules are valuable for a better understanding of collisions of protons or electrons, a subject with many applications. An antiproton is unique as' a stable, negative heavy particle without electronic structure, and it provides an excellent opportunity to study atomic collision theory. -
Confinement of Antihydrogen for 1000 Seconds
Confinement of antihydrogen for 1000 seconds G.B. Andresen1, M.D. Ashkezari2, M. Baquero-Ruiz3, W. Bertsche4, E. Butler5, C.L. Cesar6, A. Deller4, S. Eriksson4, J. Fajans3#, T. Friesen7, M.C. Fujiwara8,7, D.R. Gill8, A. Gutierrez9, J.S. Hangst1, W.N. Hardy9, R.S. Hayano10, M.E. Hayden2, A.J. Humphries4, R. Hydomako7, S. Jonsell11, S. Kemp5§, L. Kurchaninov8, N. Madsen4, S. Menary12, P. Nolan13, K. Olchanski8, A. Olin8&, P. Pusa13, C.Ø. Rasmussen1, F. Robicheaux14, E. Sarid15, D.M. Silveira16, C. So3, J.W. Storey8$, R.I. Thompson7, D.P. van der Werf4, J.S. Wurtele3#, Y. Yamazaki16¶. 1Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark. 2Department of Physics, Simon Fraser University, Burnaby BC, V5A 1S6, Canada 3Department of Physics, University of California, Berkeley, CA 94720-7300, USA 4Department of Physics, Swansea University, Swansea SA2 8PP, United Kingdom 5Physics Department, CERN, CH-1211, Geneva 23, Switzerland 6Instituto de Fısica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-972, Brazil 7Department of Physics and Astronomy, University of Calgary, Calgary AB, T2N 1N4, Canada 8TRIUMF, 4004 Wesbrook Mall, Vancouver BC, V6T 2A3, Canada 9Department of Physics and Astronomy, University of British Columbia, Vancouver BC, V6T 1Z1, Canada 10Department of Physics, University of Tokyo, Tokyo 113-0033, Japan 11 Department of Physics, Stockholm University, SE-10691, Stockholm, Sweden 12Department of Physics and Astronomy, York University, Toronto, ON, M3J 1P3, Canada 13Department of Physics, -
Antimatter Weapons (1946-1986): from Fermi and Teller's
Antimatter weapons (1946-1986): From Fermi and Teller’s speculations to the first open scientific publications ∗ Andre Gsponer and Jean-Pierre Hurni Independent Scientific Research Institute Box 30, CH-1211 Geneva-12, Switzerland e-mail: [email protected] Version ISRI-86-10.3 June 4, 2018 Abstract We recall the early theoretical speculations on the possible explosive uses of antimatter, from 1946 to the first production of antiprotons, at Berkeley in 1955, and until the first capture of cold antiprotons, at CERN on July 17–18, 1986, as well as the circumstances of the first presentation at a scientific conference of the correct physical processes leading to the ignition of a large scale thermonuclear explosion using less than a few micrograms of antimatter as trigger, at Madrid on June 30th – July 4th, 1986. Preliminary remark This paper will be followed by by Antimatter weapons (1986-2006): From the capture of the first antiprotons to the production of cold antimatter, to appear in 2006. 1 Introduction At CERN (the European Laboratory for Particle Physics), on the evening of the 17 to the 18 of July 1986, antimatter was captured in an electromagnetic trap for arXiv:physics/0507132v2 [physics.hist-ph] 28 Oct 2005 the first time in history. Due to the relatively precarious conditions of this first ∗Expanded version of a paper published in French in La Recherche 17 (Paris, 1986) 1440– 1443; in English in The World Scientist (New Delhi, India, 1987) 74–77, and in Bulletin of Peace Proposals 19 (Oslo,1988) 444–450; and in Finnish in Antimateria-aseet (Kanssainvalinen¨ rauhantutkimuslaitos, Helsinki, 1990, ISBN 951-9193-22-7) 7–18. -
ANTIPROTON and NEUTRINO PRODUCTION ACCELERATOR TIMELINE ISSUES Dave Mcginnis August 28, 2005
ANTIPROTON AND NEUTRINO PRODUCTION ACCELERATOR TIMELINE ISSUES Dave McGinnis August 28, 2005 INTRODUCTION Most of the accelerator operating period is devoted to making antiprotons for the Collider program and accelerating protons for the NUMI program. While stacking antiprotons, the same Main Injector 120 GeV acceleration cycle is used to accelerate protons bound for the antiproton production target and protons bound for the NUMI neutrino production target. This is designated as Mixed-Mode operations. The minimum cycle time is limited by the time it takes to fill the Main Injector with two Booster batches for antiproton production and five Booster batches for neutrino production (7 x 0.067 seconds) and the Main Injector ramp rate (~ 1.5 seconds). As the antiproton stack size grows, the Accumulator stochastic cooling systems slow down which requires the cycle time to be lengthened. The lengthening of the cycle time unfortunately reduces the NUMI neutrino flux. This paper will use a simple antiproton stacking model to explore some of the tradeoffs between antiproton stacking and neutrino production. ACCUMULATOR STACKTAIL SYSTEM After the target, antiprotons are injected into the Debuncher ring where they undergo a bunch rotation and are stochastically pre-cooled for injection into the Accumulator. A fresh beam pulse injected into the Accumulator from the Debuncher is merged with previous beam pulses with the Accumulator StackTail system. This system cools and decelerates the antiprotons until the antiprotons are captured by the core cooling systems as shown in Figure 1. The antiproton flux through the Stacktail system is described by the Fokker –Plank equation ∂ψ ∂φ = − (1) ∂t ∂E where φ the flux of particles passing through the energy E and ψ is the particle density of the beam at energy E. -
ANTIMATTER a Review of Its Role in the Universe and Its Applications
A review of its role in the ANTIMATTER universe and its applications THE DISCOVERY OF NATURE’S SYMMETRIES ntimatter plays an intrinsic role in our Aunderstanding of the subatomic world THE UNIVERSE THROUGH THE LOOKING-GLASS C.D. Anderson, Anderson, Emilio VisualSegrè Archives C.D. The beginning of the 20th century or vice versa, it absorbed or emitted saw a cascade of brilliant insights into quanta of electromagnetic radiation the nature of matter and energy. The of definite energy, giving rise to a first was Max Planck’s realisation that characteristic spectrum of bright or energy (in the form of electromagnetic dark lines at specific wavelengths. radiation i.e. light) had discrete values The Austrian physicist, Erwin – it was quantised. The second was Schrödinger laid down a more precise that energy and mass were equivalent, mathematical formulation of this as described by Einstein’s special behaviour based on wave theory and theory of relativity and his iconic probability – quantum mechanics. The first image of a positron track found in cosmic rays equation, E = mc2, where c is the The Schrödinger wave equation could speed of light in a vacuum; the theory predict the spectrum of the simplest or positron; when an electron also predicted that objects behave atom, hydrogen, which consists of met a positron, they would annihilate somewhat differently when moving a single electron orbiting a positive according to Einstein’s equation, proton. However, the spectrum generating two gamma rays in the featured additional lines that were not process. The concept of antimatter explained. In 1928, the British physicist was born. -
Antiproton–Proton Scattering Experiments with Polarization ( Collaboration) PAX Abstract
Technical Proposal for Antiproton–Proton Scattering Experiments with Polarization ( Collaboration) PAX arXiv:hep-ex/0505054v1 17 May 2005 J¨ulich, May 2005 2 Technical Proposal for PAX Frontmatter 3 Technical Proposal for Antiproton–Proton Scattering Experiments with Polarization ( Collaboration) PAX Abstract Polarized antiprotons, produced by spin filtering with an internal polarized gas target, provide access to a wealth of single– and double–spin observables, thereby opening a new window to physics uniquely accessible at the HESR. This includes a first measurement of the transversity distribution of the valence quarks in the proton, a test of the predicted opposite sign of the Sivers–function, related to the quark dis- tribution inside a transversely polarized nucleon, in Drell–Yan (DY) as compared to semi–inclusive DIS, and a first measurement of the moduli and the relative phase of the time–like electric and magnetic form factors GE,M of the proton. In polarized and unpolarized pp¯ elastic scattering, open questions like the contribution from the odd charge–symmetry Landshoff–mechanism at large t and spin–effects in the extraction | | of the forward scattering amplitude at low t can be addressed. The proposed de- | | tector consists of a large–angle apparatus optimized for the detection of DY electron pairs and a forward dipole spectrometer with excellent particle identification. The design and performance of the new components, required for the polarized antiproton program, are outlined. A low–energy Antiproton Polarizer Ring (APR) yields an antiproton beam polarization of Pp¯ = 0.3 to 0.4 after about two beam life times, which is of the order of 5–10 h. -
Antihydrogen and the Antiproton Magnetic Moment
Gabrielse ATRAP: Context and Status Antihydrogen and the Antiproton Magnetic Moment Gerald Gabrielse Spokesperson for TRAP and ATRAP at CERN Levere tt Pro fesso r o f Phys ics, Har var d Uni ver sit y Gabrielse Context CERN Pursues Fundamental Particle Physics at WWeveegySceseesghatever Energy Scale is Interesting A Long and Noble CERN Tradition 1981 – traveled to Fermilab “TEV or bust” 1985 – different response at CERN wh en I went th ere to try to get access to LEAR antiprotons for qqyg/m measurements and cold antihydrogen It is exciting that there is now • a dedicated storaggge ring for antih ygpydrogen experiments • four international collaborations • too few antiprotons for the demand Gabrielse Pursuing Fundamental Particle Physics atWhtt Whatever Energy Sca le is In teres ting A Long and Noble CERN Tradition 1986 – First trapped antiprotons (TRAP) 1989 – First electron-cooling of trapped antiprotons (TRAP) 1 cm magnetic field 21 MeV antiprotons slow in matter degrader _ + _ CERN’s AD, plus these cold methods make antihydrogen possible Gabrielse Pursuing Fundamental Particle Physics atWhtt Whatever Energy Sca le is In teres ting A Long and Noble CERN Tradition 1981 – traveled to Fermilab “TEV or bust” 1985 – different response at CERN when I went there to try to get access to LEAR antiprotons for q/m measurements and cold antihydrogen LHC: 7 TeV + 7 TeV AD: 5 MeV 100 times 5 x 1016 More trapped ELENA upgrade: 0.1 MeV antiprotons ATRAP: 0.3 milli-eV Gabrielse Physics With Low Energy Antiprotons First Physics: Compare q/m for antiproton -
Patentable Subject [Anti]Matter
PATENTABLE SUBJECT [ANTI]MATTER Whether antihydrogen qualifies as patentable subject matter for the purposes of the United States patent law is not an easy question. In general, man-made inventions and new compositions of matter are proper subjects of patent protection, while products of nature are not. Antihydrogen, a newly created element made entirely of antimatter, has qualities of both a newly created composition of matter and a product of nature. As a result, antihydrogen approaches the theoretical boundaries of the product of nature doctrine because mankind finally has the opportunity to create for the very first time an element that has probably never existed before in the entire universe. This iBrief will begin by briefly explaining antimatter and antihydrogen. Then, a distinction will be drawn between a man-made invention and a product of nature by analyzing relevant case law. Finally, antihydrogen will be analyzed as hypothetical subject matter under the United States patent laws without considering the further requirements of novelty and non-obviousness. An Overview of Antimatter and Antihydrogen Antimatter In 1930, the theoretical physicist Paul Dirac predicted that for every particle of matter, there exists an equivalent particle of antimatter.1 The existence of antimatter was confirmed in 1933 with the discovery of the positron, the antimatter pair of the electron.2 The theory does not mean to say that every proton in the universe must have a ghostly antiproton pair; rather it simply means that matter in the universe can be made of “real” matter, like protons and electrons, or it can be made of antimatter, like antiprotons and positrons. -
Trapped Antihydrogen in Its Ground State
Trapped Antihydrogen in Its Ground State The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Richerme, Philip. 2012. Trapped Antihydrogen in Its Ground State. Doctoral dissertation, Harvard University. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:10058466 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA ©2012 - Philip John Richerme All rights reserved. Thesis advisor Author Gerald Gabrielse Philip John Richerme Trapped Antihydrogen in Its Ground State Abstract Antihydrogen atoms (H) are confined in a magnetic quadrupole trap for 15 to 1000 s - long enough to ensure that they reach their ground state. This milestone brings us closer to the long-term goal of precise spectroscopic comparisons of H and H for tests of CPT and Lorentz invariance. Realizing trapped H requires charac- terization and control of the number, geometry, and temperature of the antiproton (p) and positron (e+) plasmas from which H is formed. An improved apparatus and implementation of plasma measurement and control techniques make available 107 p and 4 × 109 e+ for H experiments - an increase of over an order of magnitude. For the first time, p are observed to be centrifugally separated from the electrons that cool them, indicating a low-temperature, high-density p plasma. Determination of the p temperature is achieved through measurement of the p evaporation rate as their con- fining well is reduced, with corrections given by a particle-in-cell plasma simulation. -
Antihydrogen Synthesis Via Magnetobound States of Protonium Within Proton-Positron-Antiproton Plasmas
43rd EPS Conference on Plasma Physics P4.112 Antihydrogen Synthesis Via Magnetobound States of Protonium Within Proton-Positron-Antiproton Plasmas M. Hermosillo, C. A. Ordonez University of North Texas, Denton, Texas, USA Through classical trajectory simulation, the possibility that antihydrogen can be synthesized via three body recombination involving magnetobound protonium is studied. It has been previ- ously reported that proton-antiproton collisions can result in a correlated drift of the particles perpendicular to a magnetic field. While the two particles are in their correlated drift, they are referred to as a magnetobound protonium system. Possible three body recombination resulting in bound state antihydrogen is studied when a magnetobound protonium system encounters a positron. The simulation incorporates a uniform magnetic field. A visual search and an energy analysis was done in an attempt to find parameters for which the positron is captured into a bound state with an antiproton, resulting in the formation of antihydrogen. Recently, simulations have shown that within a low temperature plasma containing protons and antiprotons, binary collisons invloving proton-antiproton pairs can cause them to become bound temporarily and experience giant cross-magnetic field drifts [1, 2]. These particle pairs have been referred to as being in a magnetobound state, which could serve as a useful intermedi- ate step in the production of neutral antimatter. Magnetobound states occur in low temperatures and strong magnetic fields such as those found inside Penning traps that produce antihydrogen. The possibility of three body recombination resulting in bound state antihydrogen is studied when a magnetobound protonium system encounters a positron. The interactions between particles throughout the simulation are treated classically. -
Antihydrogen Physicsweb.Org Probing the Antiworld
Feature: Antihydrogen physicsweb.org Probing the antiworld One of the most staggering achievements in quantum physics was Paul Dirac’s prediction of the anti-electron in 1930. By tirelessly modifying Schrödinger’s descrip- tion of the electron until it was consistent with special relativity, Dirac derived a beautiful equation that had additional “negative energy” solutions. He proposed that these solutions corresponded to a particle that has the same mass as the electron but the opposite electri- cal charge. Three years later the world’s first antipar- ticle – called the positron – was discovered by Carl Anderson at the California Institute of Technology. But Dirac’s vision for antimatter did not stop there. By 1931 he had realized that the only other elementary particle known at that time – the proton – should also have a corresponding antiparticle: the antiproton. This particle was discovered at Berkeley in October 1955 (see box on page 32), setting the stage for the creation of atoms made entirely from antimatter. A positron and an antiproton form the simplest type of anti-atom – antihydrogen. However, getting these two antiparticles to come together and form a single atomic system is no mean feat, not least because anti- matter immediately annihilates when it comes into con- tact with ordinary matter. So why have physicists even bothered trying for the past 50 years? Asymmetric world When we look out at the universe from our vantage point here on Earth, one thing is clear: it is dominated by matter. Irrespective of how or where we look, anti- matter simply does not exist in the quantities we would of the properties of anti-atoms provide a unique way expect if matter and antimatter had been created in to test this once and for all. -
New Trends in the Investigation of Antiproton-Nucleus Annihilation
сообщения объединенного института ядерных исследований дубна E15-90-t50 A.M. Rozhdestvenskyк$Г/ ММ..< С.Sapozhnikov NEW TRENDS IN THE INVESTIGATION OF ANTIPROTON-NUCLEUS ANNIHILATION 1990 © Объединенный институт ядерных исследований Дубна, 1990 1. INTRODUCTION Experiments at LEAR have provided valuable information on the antiproton-nucleus interaction at low energies, T < 200 MeV (see, reviews [1,2]). Such gross features of the pA interaction as the energy dependence of cross sections, multiplicity distributions of annihilation mesons, angular and momentum spectra of outgoing particles etc. are known nov. This information provides a reference frame for future tasks to be carried out at high intensity hadron facilities such as the KAON factory or SUPERLEAR-type machines. In high energy antiproton-nucleus physics one can single out at least two types of j.rc|blems . The first involves investigation of the mechanisms of antiproton interaction with nuclei. In a certain sense it represents a repetition of the program performed with protons and pions. Such experiments are needed for a better understanding of which phenomena are to be regarded as conventional. Problems of the second type include the investigation of specific antiproton-nucleus annihilation phenomena. How does a nucleus react to a near 2 GeV energy release occurring in a small volume on the surface or inside the nucleus? How strong is the final state interaction of annihilation mesons? Is annihilation on few-nucleon clusters possible? Does the annihilation probability on a bound nucleon differ from the annihilation probability on a free nucleon? All these problems represent examples of "pure" antiproton physics. We believe it is these aspects of antiproton-nucleus physics that will become more and more important in the future.