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Pramana

, Volume 61, Issue 5, pp 865–876 | Cite as

PHOBOS at RHIC: Some global observations

  • Alan S. Carroll
  • For the PHOBOS Collaboration
  • B. B. Back
  • M. D. Baker
  • D. S. Barton
  • R. R. Betts
  • M. Ballintijn
  • A. A. Bickley
  • R. Bindel
  • A. Budzanowski
  • W. Busza
  • A. Carroll
  • M. P. Decowski
  • E. García
  • N. George
  • K. Gulbrandsen
  • S. Gushue
  • C. Halliwell
  • J. Hamblen
  • G. A. Heintzelman
  • C Henderson
  • D. J. Hofman
  • R. S. Hollis
  • R. Hoyłyński
  • B. Holzman
  • A. Iordanova
  • E. Johnson
  • J. L. Kane
  • J. Katzy
  • N. Khan
  • W. Kucewicz
  • P. Kulinich
  • C. M. Kuo
  • W. T. Lin
  • S. Manly
  • D. McLeod
  • J. Michałowski
  • A. C. Mignerey
  • R. Nouicer
  • A. Olszewski
  • R. Pak
  • I. C. Park
  • H. Pernegger
  • C. Reed
  • L. P. Remsberg
  • M. Reuter
  • C. Roland
  • G. Roland
  • L. Rosenberg
  • J. Sagerer
  • P. Sarin
  • P. Sawicki
  • W. Skulski
  • S. G. Steadman
  • P. Steinberg
  • G. S. F. Stephans
  • M. Stodulski
  • A. Sukhanov
  • J.-L. Tang
  • R. Teng
  • A. Trzupek
  • C. Vale
  • G. J. van Nieuwenhuizen
  • R. Verdier
  • B. Wadsworth
  • F. L. H. Wolfs
  • B. Wosiek
  • K. Woźniak
  • A. H. Wuosmaa
  • B. Wysłouch
Article

Abstract

Particle production in Au+Au collisions has been measured in the PHOBOS experiment at RHIC for a range of collision energies for a large span of pseudorapidities, |η| < 5.4. Three empirical observations have emerged from this data set which require theoretical examination. First, there is clear evidence of limiting fragmentation. Namely, particle production in central Au + Au collisions, when expressed as dN/dη′ ( η′ ≡ – ybeam), becomes energy independent at high energy for a broad region of η′ around η′ = 0. This energy-independent region grows with energy, allowing only a limited region (if any) of longitudinal boost-invariance. Second, there is a striking similarity between particle production in e+eand Au + Au collisions (scaled by the number of participating nucleon pairs). Both the total number of produced particles and the longitudinal distribution of produced particles are approximately the same in e+eand in scaled Au + Au. This observation This presentation is based in large part on the PHOBOS summary talk by M Baker at the16th Int. Conf. on Ultrarelativistic Nucleus- Nucleus Collisions, Quark Matter 2002, Nantes, France was not predicted and has not been explained. Finally, particle production has been found to scale approximately with the number of participating nucleon pairs for (N part ) > 65. This scaling occurs both for the total multiplicity and for highp T particles (3 <p T < 4.5 GeV/c).

Keywords

Heavy ion multiplicity comparison PHOBOS RHIC. 

PACS Nos.

25.75.Dw 25.75.Nq 

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References

  1. [1]
    B B Backet al,Nucl. Instrum. Methods, to be publishedGoogle Scholar
  2. [1a]
    R Nouiceret al, Nucl. Instrum. Methods A461, 143 (2001)ADSGoogle Scholar
  3. [1b]
    B B Backet al, Nucl. Phys. A698, 416c (2002)ADSGoogle Scholar
  4. [2]
    B B Backet al, Phys. Rev. Lett. 85, 3100 (2000)CrossRefADSGoogle Scholar
  5. [3]
    B B Backet al, Phys. Rev. C65, 061901R (2002)ADSGoogle Scholar
  6. [4]
    B B Backet al, arXiv: nucl-ex/0210015;Phys. Rev. Lett. (submitted)Google Scholar
  7. [5]
    B B Backet al, arXiv:nucl-ex/0205021;Phys. Rev. Lett. (in press)Google Scholar
  8. [6]
    S Manlyet al, Proceedings of 16th International Conference on Ultrarelativistic Nucleus- Nucleus Collisions (Quark Matter 2002 (QM 2002), Nantes, France); arXiv:nucl-ex/0210036Google Scholar
  9. [7]
    B Wosieket al, Proceedings of 16th International Conference on Ultrarelativistic Nucleus- Nucleus Collisions (Quark Matter 2002 (QM 2002), Nantes, France); arXiv:nucl-ex/0210037Google Scholar
  10. [8]
    J Benecke, T T Chou, C-N Yang and E Yen,Phys. Rev. 188, 2159 (1969)CrossRefADSGoogle Scholar
  11. [9]
    J E Eliaset al, Phys. Rev. D22, 13 (1980)ADSMathSciNetGoogle Scholar
  12. [10]
    G J Alneret al, Z. Phys. C33, 1 (1986)Google Scholar
  13. [11]
    I G Beardenet al, Phys. Rev. Lett. 88, 202301 (2002)CrossRefADSGoogle Scholar
  14. [12]
    J D Bjorken,Phys. Rev. D27, 140 (1983)ADSGoogle Scholar
  15. [13]
    PA Steinberget al, Proceedings of 16th International Conference on Ultrarelativistic Nucleus- Nucleus Collisions (Quark Matter 2002 (QM 2002), Nantes, France); arXiv:nucl-ex/0211002 B B Backet al, Phys. Rev. Lett. (submitted); arXiv:nucl-ex/0301017Google Scholar
  16. [14]
    J Klay and U C Davis, Ph.D. Thesis (2001) S V Afanasievet al, arXiv:nucl-ex/0205002 (2002)Google Scholar
  17. [14]
    D E Groomet al, Euro. Phys. J. C15, 1 (2000)Google Scholar
  18. [15]
    A H Mueller,Nucl. Phys. B213, 85 (1983)CrossRefADSGoogle Scholar
  19. [16]
    M Basileet al, Phys. Lett. B92, 367 (1980)ADSGoogle Scholar
  20. [16a]
    M Basileet al, Phys. Lett. B95, 311 (1980)ADSGoogle Scholar
  21. [17]
    P Abreuet al, Phys. Lett. B459, 397 (1999)ADSGoogle Scholar
  22. [18]
    J E Eliaset al, Phys. Rev. Lett. 41, 285 (1978)CrossRefADSGoogle Scholar
  23. [18a]
    A Białas, B Bleszyński and W Czyz,Nucl. Phys. B111, 461 (1976)ADSGoogle Scholar
  24. [19]
    D Kharzeev and M Nardi,Phys. Lett. B507, 121 (2001)ADSGoogle Scholar
  25. [20]
    D Kharzeev and E Levin,Phys. Lett. B523, 79 (2001) D Kharzeev, E Levin and M Nardi; arXiv:hep-ph/0111315ADSGoogle Scholar
  26. [21]
    K Adcoxet al, Phys. Rev. Lett. 88, 022301 (2002)CrossRefADSGoogle Scholar
  27. [21a]
    C Adleret al, Phys. Rev. Lett. 89, 202301 (2002)CrossRefADSGoogle Scholar
  28. [22]
    C Rolandet al, Proceedings of 16th International Conference on Ultrarelativistic Nucleus- Nucleus Collisions (Quark Matter 2002 (QM 2002), Nantes, France)Google Scholar
  29. [23]
    K Adcoxet al, arXiv:nucl-ex/0207009 (2002);Phys. Lett. B (submitted)Google Scholar
  30. [24]
    C Adleret al, Phys. Rev. Lett. 90, 082302 (2003)CrossRefADSGoogle Scholar

Copyright information

© Indian Academy of Sciences 2003

Authors and Affiliations

  • Alan S. Carroll
    • 1
  • For the PHOBOS Collaboration
  • B. B. Back
    • 1
  • M. D. Baker
    • 2
  • D. S. Barton
    • 2
  • R. R. Betts
    • 6
  • M. Ballintijn
    • 4
  • A. A. Bickley
    • 7
  • R. Bindel
    • 7
  • A. Budzanowski
    • 3
  • W. Busza
    • 4
  • A. Carroll
    • 2
  • M. P. Decowski
    • 4
  • E. García
    • 6
  • N. George
    • 2
  • K. Gulbrandsen
    • 4
  • S. Gushue
    • 2
  • C. Halliwell
    • 6
  • J. Hamblen
    • 8
  • G. A. Heintzelman
    • 2
  • C Henderson
  • D. J. Hofman
    • 6
  • R. S. Hollis
    • 6
  • R. Hoyłyński
    • 3
  • B. Holzman
    • 2
  • A. Iordanova
    • 6
  • E. Johnson
    • 8
  • J. L. Kane
    • 4
  • J. Katzy
    • 4
    • 6
  • N. Khan
    • 8
  • W. Kucewicz
    • 6
  • P. Kulinich
    • 4
  • C. M. Kuo
    • 5
  • W. T. Lin
    • 5
  • S. Manly
    • 8
  • D. McLeod
    • 6
  • J. Michałowski
    • 3
  • A. C. Mignerey
    • 7
  • R. Nouicer
    • 6
  • A. Olszewski
    • 3
  • R. Pak
    • 2
  • I. C. Park
    • 8
  • H. Pernegger
    • 4
  • C. Reed
    • 4
  • L. P. Remsberg
    • 2
  • M. Reuter
    • 6
  • C. Roland
    • 4
  • G. Roland
    • 4
  • L. Rosenberg
    • 4
  • J. Sagerer
    • 6
  • P. Sarin
    • 4
  • P. Sawicki
    • 3
  • W. Skulski
    • 8
  • S. G. Steadman
    • 4
  • P. Steinberg
    • 2
  • G. S. F. Stephans
    • 4
  • M. Stodulski
    • 3
  • A. Sukhanov
    • 2
  • J.-L. Tang
    • 5
  • R. Teng
    • 8
  • A. Trzupek
    • 3
  • C. Vale
    • 4
  • G. J. van Nieuwenhuizen
    • 4
  • R. Verdier
    • 4
  • B. Wadsworth
    • 4
  • F. L. H. Wolfs
    • 8
  • B. Wosiek
    • 3
  • K. Woźniak
    • 3
  • A. H. Wuosmaa
    • 1
  • B. Wysłouch
    • 4
  1. 1.Argonne National LaboratoryArgonneUSA
  2. 2.Brookhaven National LaboratoryUptonUSA
  3. 3.Institute of Nuclear PhysicsKrakówPoland
  4. 4.Massachusetts Institute of TechnologyCambridgeUSA
  5. 5.National Central UniversityChung-LiTaiwan
  6. 6.University of Illinois at ChicagoChicagoUSA
  7. 7.University of MarylandUSA
  8. 8.University of RochesterRochesterUSA

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