Apex and the e+/e Puzzle: Recent Results

  • I. Ahmad
  • S. M. Austin
  • B. B. Back
  • R. R. Betts
  • F. P. Calaprice
  • K. C. Chan
  • A. Chishti
  • P. Chowdhury
  • C. Conner
  • R. W. Dunford
  • J. D. Fox
  • S. J. Freedman
  • M. Freer
  • S. Gazes
  • A. L. Hallin
  • T. Happ
  • N. I. Kaloskamis
  • E. Kashy
  • W. Kutschera
  • J. Last
  • C. J. Lister
  • M. Liu
  • M. R. Maier
  • D. J. Mercer
  • D. Mikolas
  • P. A. A. Perera
  • M. D. Rhein
  • D. E. Roa
  • J. P. Schiffer
  • T. A. Trainor
  • P. Wilt
  • J. S. Winfield
  • M. Wolanski
  • F. L. H. Wolfs
  • A. H. Wuosmaa
  • A. Young
  • J. E. Yurkon

Abstract

Narrow structures first reported in positron singles energy spectra [1, 2, 3, 4, 5, 6, 7] and later in electron-positron energy distributions [5, 8, 9, 10, 11, 12] associated with collisions of very heavy ions near the Coulomb barrier have been an outstanding puzzle in nuclear physics for nearly fifteen years. In a series of positron and positron/electron experiments by three different groups (EPOS, ORANGE and TORI) ([5] and citations therein) at the GSI UNILAC at Darmstadt, Germany narrow structures (‘lines’) were observed by EPOS and ORANGE for several heavy-ion collision systems, with some features such as the line energies and widths having apparently similar values for the different collision systems.

Keywords

Monte Carlo Integrate Luminosity Peak Yield Peak Pair Collision System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • I. Ahmad
    • 1
  • S. M. Austin
    • 2
  • B. B. Back
    • 1
  • R. R. Betts
    • 1
    • 3
  • F. P. Calaprice
    • 4
  • K. C. Chan
    • 5
  • A. Chishti
    • 5
  • P. Chowdhury
    • 5
  • C. Conner
    • 3
  • R. W. Dunford
    • 1
  • J. D. Fox
    • 6
  • S. J. Freedman
    • 1
    • 7
  • M. Freer
    • 1
    • 8
  • S. Gazes
    • 9
    • 10
  • A. L. Hallin
    • 11
  • T. Happ
    • 1
    • 12
  • N. I. Kaloskamis
    • 5
    • 13
  • E. Kashy
    • 2
  • W. Kutschera
    • 1
  • J. Last
    • 1
  • C. J. Lister
    • 1
    • 5
  • M. Liu
    • 11
  • M. R. Maier
    • 7
  • D. J. Mercer
    • 2
  • D. Mikolas
    • 2
  • P. A. A. Perera
    • 10
  • M. D. Rhein
    • 1
    • 12
  • D. E. Roa
    • 6
  • J. P. Schiffer
    • 1
    • 9
  • T. A. Trainor
    • 14
  • P. Wilt
    • 1
  • J. S. Winfield
    • 2
  • M. Wolanski
    • 1
    • 9
  • F. L. H. Wolfs
    • 10
  • A. H. Wuosmaa
    • 1
  • A. Young
    • 4
  • J. E. Yurkon
    • 2
  1. 1.Physics DivisionArgonne National LaboratoryArgonneUSA
  2. 2.NSCLMichigan State UniversityEast LansingUSA
  3. 3.Dept. of PhysicsUniversity of Illinois at ChicagoChicagoUSA
  4. 4.Physics Dept.Princeton UniversityPrincetonUSA
  5. 5.WNSLYale UniversityNew HavenUSA
  6. 6.Physics Dept.Florida State UniversityTallahasseeUSA
  7. 7.LBNLBerkeleyUSA
  8. 8.Dept. of PhysicsUniversity of BirminghamBirminghamUK
  9. 9.Dept. of PhysicsUniversity of ChicagoChicagoUSA
  10. 10.NSRLUniversity of RochesterRochesterUSA
  11. 11.Physics Dept.Queen’s UniversityKingstonCanada
  12. 12.GSIPlanckstrasse 1DarmstadtGermany
  13. 13.Dept. of PhysicsUniversity of Notre DameNotre DameUSA
  14. 14.NPLUniversity of WashingtonSeattleUSA

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