Observation of Antiprotons
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(Anti)Proton Mass and Magnetic Moment
FFK Conference 2019, Tihany, Hungary Precision measurements of the (anti)proton mass and magnetic moment Wolfgang Quint GSI Darmstadt and University of Heidelberg on behalf of the BASE collaboration spokesperson: Stefan Ulmer 2019 / 06 / 12 BASE – Collaboration • Mainz: Measurement of the magnetic moment of the proton, implementation of new technologies. • CERN Antiproton Decelerator: Measurement of the magnetic moment of the antiproton and proton/antiproton q/m ratio • Hannover/PTB: Laser cooling project, new technologies Institutes: RIKEN, MPI-K, CERN, University of Mainz, Tokyo University, GSI Darmstadt, University of Hannover, PTB Braunschweig C. Smorra et al., EPJ-Special Topics, The BASE Experiment, (2015) WE HAVE A PROBLEM mechanism which created the obvious baryon/antibaryon asymmetry in the Universe is not understood One strategy: Compare the fundamental properties of matter / antimatter conjugates with ultra-high precision CPT tests based on particle/antiparticle comparisons R.S. Van Dyck et al., Phys. Rev. Lett. 59 , 26 (1987). Recent B. Schwingenheuer, et al., Phys. Rev. Lett. 74, 4376 (1995). Past CERN H. Dehmelt et al., Phys. Rev. Lett. 83 , 4694 (1999). G. W. Bennett et al., Phys. Rev. D 73 , 072003 (2006). Planned M. Hori et al., Nature 475 , 485 (2011). ALICE G. Gabriesle et al., PRL 82 , 3199(1999). J. DiSciacca et al., PRL 110 , 130801 (2013). S. Ulmer et al., Nature 524 , 196-200 (2015). ALICE Collaboration, Nature Physics 11 , 811–814 (2015). M. Hori et al., Science 354 , 610 (2016). H. Nagahama et al., Nat. Comm. 8, 14084 (2017). M. Ahmadi et al., Nature 541 , 506 (2017). M. Ahmadi et al., Nature 586 , doi:10.1038/s41586-018-0017 (2018). -
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. -
BOTTOM, STRANGE MESONS (B = ±1, S = ∓1) 0 0 ∗ Bs = Sb, Bs = S B, Similarly for Bs ’S
Citation: P.A. Zyla et al. (Particle Data Group), Prog. Theor. Exp. Phys. 2020, 083C01 (2020) BOTTOM, STRANGE MESONS (B = ±1, S = ∓1) 0 0 ∗ Bs = sb, Bs = s b, similarly for Bs ’s 0 P − Bs I (J ) = 0(0 ) I , J, P need confirmation. Quantum numbers shown are quark-model predictions. Mass m 0 = 5366.88 ± 0.14 MeV Bs m 0 − mB = 87.38 ± 0.16 MeV Bs Mean life τ = (1.515 ± 0.004) × 10−12 s cτ = 454.2 µm 12 −1 ∆Γ 0 = Γ 0 − Γ 0 = (0.085 ± 0.004) × 10 s Bs BsL Bs H 0 0 Bs -Bs mixing parameters 12 −1 ∆m 0 = m 0 – m 0 = (17.749 ± 0.020) × 10 ¯h s Bs Bs H BsL = (1.1683 ± 0.0013) × 10−8 MeV xs = ∆m 0 /Γ 0 = 26.89 ± 0.07 Bs Bs χs = 0.499312 ± 0.000004 0 CP violation parameters in Bs 2 −3 Re(ǫ 0 )/(1+ ǫ 0 )=(−0.15 ± 0.70) × 10 Bs Bs 0 + − CKK (Bs → K K )=0.14 ± 0.11 0 + − SKK (Bs → K K )=0.30 ± 0.13 0 ∓ ± +0.10 rB(Bs → Ds K )=0.37−0.09 0 ± ∓ ◦ δB(Bs → Ds K ) = (358 ± 14) −2 CP Violation phase βs = (2.55 ± 1.15) × 10 rad λ (B0 → J/ψ(1S)φ)=1.012 ± 0.017 s λ = 0.999 ± 0.017 A, CP violation parameter = −0.75 ± 0.12 C, CP violation parameter = 0.19 ± 0.06 S, CP violation parameter = 0.17 ± 0.06 L ∗ 0 ACP (Bs → J/ψ K (892) ) = −0.05 ± 0.06 k ∗ 0 ACP (Bs → J/ψ K (892) )=0.17 ± 0.15 ⊥ ∗ 0 ACP (Bs → J/ψ K (892) ) = −0.05 ± 0.10 + − ACP (Bs → π K ) = 0.221 ± 0.015 0 + − ∗ 0 ACP (Bs → [K K ]D K (892) ) = −0.04 ± 0.07 HTTP://PDG.LBL.GOV Page1 Created:6/1/202008:28 Citation: P.A. -
1.1. Introduction the Phenomenon of Positron Annihilation Spectroscopy
PRINCIPLES OF POSITRON ANNIHILATION Chapter-1 __________________________________________________________________________________________ 1.1. Introduction The phenomenon of positron annihilation spectroscopy (PAS) has been utilized as nuclear method to probe a variety of material properties as well as to research problems in solid state physics. The field of solid state investigation with positrons started in the early fifties, when it was recognized that information could be obtained about the properties of solids by studying the annihilation of a positron and an electron as given by Dumond et al. [1] and Bendetti and Roichings [2]. In particular, the discovery of the interaction of positrons with defects in crystal solids by Mckenize et al. [3] has given a strong impetus to a further elaboration of the PAS. Currently, PAS is amongst the best nuclear methods, and its most recent developments are documented in the proceedings of the latest positron annihilation conferences [4-8]. PAS is successfully applied for the investigation of electron characteristics and defect structures present in materials, magnetic structures of solids, plastic deformation at low and high temperature, and phase transformations in alloys, semiconductors, polymers, porous material, etc. Its applications extend from advanced problems of solid state physics and materials science to industrial use. It is also widely used in chemistry, biology, and medicine (e.g. locating tumors). As the process of measurement does not mostly influence the properties of the investigated sample, PAS is a non-destructive testing approach that allows the subsequent study of a sample by other methods. As experimental equipment for many applications, PAS is commercially produced and is relatively cheap, thus, increasingly more research laboratories are using PAS for basic research, diagnostics of machine parts working in hard conditions, and for characterization of high-tech materials. -
Remembering Alvin Tollestrup: 1924-2020 – CERN Courier
3/26/2020 Remembering Alvin Tollestrup: 1924-2020 – CERN Courier PEOPLE | NEWS Remembering Alvin Tollestrup: 1924-2020 6 March 2020 Alvin Tollestrup, who passed away on 9 February at the age of 95, was a visionary. When I joined his group at Caltech in the summer of 1960, experiments in particle physics at universities were performed at accelerators located on campus. Alvin had helped build Caltech’s electron synchrotron, the highest energy photon-producing accelerator at the time. But he thought more exciting physics could be performed elsewhere, and managed to get approval to run an experiment at Berkeley Lab’s Bevatron to measure a rare decay mode of the K+ meson. This was the rst time an outsider was allowed to access Berkeley’s machine, much to the consternation of Luis Alvarez and other university faculty. When I joined Alvin’s group he asked a postdoc, Ricardo Gomez, and me to design, build and test https://cerncourier.com/a/remembering-alvin-tollestrup-1924-2020/ 1/5 3/26/2020 Remembering Alvin Tollestrup: 1924-2020 – CERN Courier Machine maestro – Alvin Tollestrup led the pioneering a new type of particle detector called a spark work of designing and testing the superconducting magnets for the Tevatron, the rst large-scale chamber. He gave us a paper by two Japanese application of superconductivity. Credit: Fermilab authors on “A new type of particle detector: the discharge chamber”, not what he wanted, but a place to start. In retrospect it was remarkable that Alvin was willing to risk the success of his experiment on the creation of new technology. -
8.701 Introduction to Nuclear and Particle Physics, Recitation 19
Massachusetts Institute of Technology Department of Physics Course: 8.701 { Introduction to Nuclear and Particle Physics Term: Fall 2020 Instructor: Markus Klute TA : Tianyu Justin Yang Discussion Problems from recitation on December 1st, 2020 Problem 1: Bubble Chamber Carl David Anderson discovered positrons in cosmic rays. The picture below shows a cloud chamber image produced by Anderson in 1931. The cloud chamber is positioned in a magnetic field of 1:5 T with field lines pointing into the plane of the paper. A cosmic ray particle enters the chamber from below and leaves a circular track. There is a 6 mm thick lead plate in the cloud chamber visible as a horizontal line. The radius of curvature is 15:5 cm before and 5:3 cm after the passage through the lead plate. 1 Figure 1: Cloud-chamber image of a positron. This image is in the public domain. a) Estimate the momentum of the particle before and after the passage through the lead plate. What is the charge of the particle? b) Compare the energy loss during the passage through the lead plate for a proton, a pions, and an electron. For the energy loss calculation, you can use the approximate Bethe formula below and assume constant energy loss. dE Z 1 m γ2 β2 c2 = −4 π N r2 m c2 z 2 ·· ln e (1) A e e 2 dX Ion A β I Explain why this is sufficient to exclude the proton and pion hypothesis. The con- 23 −1 −12 A s stants in the equation are NA = 6; 022 × 10 mol , 0 = 8; 85 × 10 V m , me = e2 511 keV, re = 2 , Z = 82, A = 207, and I = 820 eV, the ionisation energy in (4 π0)me c lead. -
Cloud Chamber Experiment
Cloud chamber experiment Teachers notes Adapted from “Science, Society and America’s Nuclear Waste – Ionising Radiation” by US Department of Energy, July 1995. Page 1 of 8 Adapted from “Science, Society and America’s Nuclear Waste – Ionising Radiation” by US Department of Energy, July 1995. Page 1 of 8 Purpose: The Cloud Chamber experiment illustrates that though radiation cannot be detected with the senses, it is possible to observe the result of radioactive decay. Concepts: 1. Radiation cannot be detected directly by using our senses, but can be indirectly detected. Duration of Lesson: One 50-minute class period. Objectives: As a result of the participation in the Cloud Chamber experience, the student will be able to: 1. Describe that as charged particles pass through the chamber, they leave an observable track much like the vapour train of a jet plane; and 2. Conclude that what he/she has observed is the result of radioactive decay. Optional Objectives: 1. Through measurement of tracks in the Cloud Chamber, the student will be able to determine which type of radiation travels furthest from its source. 2. By holding a strong magnet next to the Cloud Chamber, the student will be able to deduce what effect, if any, a magnet has on radiation. 3. By wrapping the source alternatively in paper, aluminium foil, plastic wrap and cloth, the student will be able to conclude what effect, if any, shielding has on radiation. Skills: Drawing conclusions, measuring, note-taking, observing, deductive reasoning, working in groups. Vocabulary: Alpha particle, beta particle, gamma ray. Materials: Activity Sheets The Cloud Chamber Background Notes Safe Use of Dry Ice Cloud Chamber Suggested Procedure: Adapted from “Science, Society and America’s Nuclear Waste – Ionising Radiation” by US Department of Energy, July 1995. -
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. -
Date: To: September 22, 1 997 Mr Ian Johnston©
22-SEP-1997 16:36 NOBELSTIFTELSEN 4& 8 6603847 SID 01 NOBELSTIFTELSEN The Nobel Foundation TELEFAX Date: September 22, 1 997 To: Mr Ian Johnston© Company: Executive Office of the Secretary-General Fax no: 0091-2129633511 From: The Nobel Foundation Total number of pages: olO MESSAGE DearMrJohnstone, With reference to your fax and to our telephone conversation, I am enclosing the address list of all Nobel Prize laureates. Yours sincerely, Ingr BergstrSm Mailing address: Bos StU S-102 45 Stockholm. Sweden Strat itddrtSMi Suircfatan 14 Teleptelrtts: (-MB S) 663 » 20 Fsuc (*-«>!) «W Jg 47 22-SEP-1997 16:36 NOBELSTIFTELSEN 46 B S603847 SID 02 22-SEP-1997 16:35 NOBELSTIFTELSEN 46 8 6603847 SID 03 Professor Willis E, Lamb Jr Prof. Aleksandre M. Prokhorov Dr. Leo EsaJki 848 North Norris Avenue Russian Academy of Sciences University of Tsukuba TUCSON, AZ 857 19 Leninskii Prospect 14 Tsukuba USA MSOCOWV71 Ibaraki Ru s s I a 305 Japan 59* c>io Dr. Tsung Dao Lee Professor Hans A. Bethe Professor Antony Hewlsh Department of Physics Cornell University Cavendish Laboratory Columbia University ITHACA, NY 14853 University of Cambridge 538 West I20th Street USA CAMBRIDGE CB3 OHE NEW YORK, NY 10027 England USA S96 014 S ' Dr. Chen Ning Yang Professor Murray Gell-Mann ^ Professor Aage Bohr The Institute for Department of Physics Niels Bohr Institutet Theoretical Physics California Institute of Technology Blegdamsvej 17 State University of New York PASADENA, CA91125 DK-2100 KOPENHAMN 0 STONY BROOK, NY 11794 USA D anni ark USA 595 600 613 Professor Owen Chamberlain Professor Louis Neel ' Professor Ben Mottelson 6068 Margarldo Drive Membre de rinstitute Nordita OAKLAND, CA 946 IS 15 Rue Marcel-Allegot Blegdamsvej 17 USA F-92190 MEUDON-BELLEVUE DK-2100 KOPENHAMN 0 Frankrike D an m ar k 599 615 Professor Donald A. -
Particle Detectors Lecture Notes
Lecture Notes Heidelberg, Summer Term 2011 The Physics of Particle Detectors Hans-Christian Schultz-Coulon Kirchhoff-Institut für Physik Introduction Historical Developments Historical Development γ-rays First 1896 Detection of α-, β- and γ-rays 1896 β-rays Image of Becquerel's photographic plate which has been An x-ray picture taken by Wilhelm Röntgen of Albert von fogged by exposure to radiation from a uranium salt. Kölliker's hand at a public lecture on 23 January 1896. Historical Development Rutherford's scattering experiment Microscope + Scintillating ZnS screen Schematic view of Rutherford experiment 1911 Rutherford's original experimental setup Historical Development Detection of cosmic rays [Hess 1912; Nobel prize 1936] ! "# Electrometer Cylinder from Wulf [2 cm diameter] Mirror Strings Microscope Natrium ! !""#$%&'()*+,-)./0)1&$23456/)78096$/'9::9098)1912 $%&!'()*+,-.%!/0&1.)%21331&10!,0%))0!%42%!56784210462!1(,!9624,10462,:177%&!(2;! '()*+,-.%2!<=%4*1;%2%)%:0&67%0%&!;1&>!Victor F. Hess before his 1912 balloon flight in Austria during which he discovered cosmic rays. ?40! @4)*%! ;%&! /0%)),-.&1(8%! A! )1,,%2! ,4-.!;4%!BC;%2!;%,!D)%:0&67%0%&,!(7!;4%! EC2F,1-.,%!;%,!/0&1.)%21331&10,!;&%.%2G!(7!%42%!*H&!;4%!A8)%,(2F!FH2,04F%!I6,40462! %42,0%))%2! J(! :K22%2>! L10&4(7! =4&;! M%&=%2;%0G! (7! ;4%! E(*0! 47! 922%&%2! ;%,! 9624,10462,M6)(7%2!M62!B%(-.04F:%40!*&%4!J(!.1)0%2>! $%&!422%&%G!:)%42%&%!<N)42;%&!;4%20!;%&!O8%&3&H*(2F!;%&!9,6)10462!;%,!P%&C0%,>!'4&;!%&! H8%&! ;4%! BC;%2! F%,%2:0G! ,6! M%&&42F%&0! ,4-.!;1,!1:04M%!9624,10462,M6)(7%2!1(*!;%2! -
Accelerator Disaster Scenarios, the Unabomber, and Scientific Risks
Accelerator Disaster Scenarios, the Unabomber, and Scientific Risks Joseph I. Kapusta∗ Abstract The possibility that experiments at high-energy accelerators could create new forms of matter that would ultimately destroy the Earth has been considered several times in the past quarter century. One consequence of the earliest of these disaster scenarios was that the authors of a 1993 article in Physics Today who reviewed the experi- ments that had been carried out at the Bevalac at Lawrence Berkeley Laboratory were placed on the FBI's Unabomber watch list. Later, concerns that experiments at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory might create mini black holes or nuggets of stable strange quark matter resulted in a flurry of articles in the popular press. I discuss this history, as well as Richard A. Pos- ner's provocative analysis and recommendations on how to deal with such scientific risks. I conclude that better communication between scientists and nonscientists would serve to assuage unreasonable fears and focus attention on truly serious potential threats to humankind. Key words: Wladek Swiatecki; Subal Das Gupta; Gary D. Westfall; Theodore J. Kaczynski; Frank Wilczek; John Marburger III; Richard A. Posner; Be- valac; Relativistic Heavy Ion Collider (RHIC); Large Hadron Collider (LHC); Lawrence Berkeley National Laboratory; Brookhaven National Laboratory; CERN; Unabomber; Federal Bureau of Investigation; nuclear physics; accel- erators; abnormal nuclear matter; density isomer; black hole; strange quark matter; scientific risks. arXiv:0804.4806v1 [physics.hist-ph] 30 Apr 2008 ∗Joseph I. Kapusta received his Ph.D. degree at the University of California at Berkeley in 1978 and has been on the faculty of the School of Physics and Astronomy at the University of Minnesota since 1982. -
Types of Radiation: the Patterns They Produce in a Cloud Chamber
430 THEAMERICAN BIOLOGY TEACHER the National Bureau of Standards available from No. 51, Radiological Monitoring Methods and the Superintendent of Documents, Government Instruments, $.20. Printing Office, Washington 25, D. C., at the prices No. 69, Maximum Permissible Body Burdens and indicated. Maximum Permissible concentrations of No. 42, Safe Handling of Radioactive Isotopes, Radionucleides in Air and in Water for $.20 Occupational Exposure, $.35. No. 48, Control and Removal of Radioactive No. 80, A Manual of Radioactivity Procedures, Contamination in Laboratories, $.15. $.50. Types of Radiation-the PatternsThey Produce in a CloudChamber Downloaded from http://online.ucpress.edu/abt/article-pdf/27/6/430/21573/4441004.pdf by guest on 28 September 2021 * C. T. Lange, ClaytonHigh School, Clayton,Missouri, and Glen Farrell,Holt, Rinehartand Winston,San Francisco,California A description of the practical uses of a cloud chamber is followed by the instructions for the building and use of an inexpensive cloud chamber in the classroom. Introduction a biologist, yet we can use it to help build a Every minute of the day, whether we basic understanding of the nature and prop- realize it or not, we are being pelted by an erties of ionizing radiations. The cloud invisible stream of very high energy particles chamber was the tool which Rutherford used known as cosmic rays. The number of these to study transmutation of one element to striking our body is about one thousand per another. He observed that nitrogen atoms minute. We also are being subjected to the under alpha particle bombardment were alpha, beta, and gamma radiations from changed into oxygen and hydrogen.