- Physical Review Journals
All JournalsPhysics Magazine
Access Provided by Xinjiang University

Physical Review D

Export citation

Export citation

Choose format for download:

Download Citation
  • Access by Xinjiang University

Nonfactorizable effects in top quark production

Jonathan L. Rosner

  • Enrico Fermi Institute and Department of Physics, University of Chicago, 5620 S. Ellis Avenue, Chicago, Illinois 60637, USA

PDF

Phys. Rev. D 86, 014011 – Published 11 July, 2012

DOI: https://doi.org/10.1103/PhysRevD.86.014011

Abstract

The production of top-antitop pairs at the Fermilab Tevatron shows a forward-backward asymmetry in which the top quark tends to follow the proton direction, while the antitop tends to follow the antiproton direction. The effect grows with increasing effective mass mtt¯ of the top-antitop pair, and with increasing rapidity difference between the top and antitop. The observed effect is about 3 times as large as predicted by next-to-leading-order QCD, but with the same sign. An estimate of nonfactorizable effects based on a QCD string picture finds they are negligible, but that small distortions of the mt spectrum are possible. Tests for such effects, both at and above the level of this estimate, are suggested.

View figure in article

Article Text

References (26)

  1. T. Aaltonen et al. (CDF Collaboration), Phys. Rev. D 83, 112003 (2011); CDF Conference Notes No. 10436 and No. 10584, 2011.
  2. D. Mietlicki, Joint Experimental-Theoretical Physics Seminar, Fermilab, 2012.
  3. V. M. Abazov et al. (D0 Collaboration), Phys. Rev. D 84, 112005 (2011).
  4. S. Frixione, G. Ridolfi, and P. Nason, J. High Energy Phys. 09 (2007) 126; N. Kidonakis, Phys. Rev. D 84, 011504 (2011); V. Ahrens, A. Ferroglia, M. Neubert, B. D. Pecjak, and L. L. Yang, 84, 074004 (2011); W. Hollik and D. Pagani, 84, 093003 (2011); J. Kühn and G. Rodrigo, J. High Energy Phys. 01 (2012) 063; A. V. Manohar and M. Trott, Phys. Lett. B 711, 313 (2012).
  5. See, e.g., the following and references therein: Q.-H. Cao, D. McKeen, J. L. Rosner, G. Shaughnessy, and C. E. M. Wagner, Phys. Rev. D 81, 114004 (2010); M. Gresham, I. W. Kim, and K. Zurek, 84, 034025 (2011); D. Duffy, Z. Sullivan, and H. Zhang, 85, 094027 (2012).
  6. P. Z. Skands and D. Wicke, Eur. Phys. J. C 52, 133 (2007).
  7. G. Gustafson, U. Pettersson, and P. M. Zerwas, Phys. Lett. B 209, 90 (1988); B. R. Webber, J. Phys. G 24, 287 (1998).
  8. See, e.g., P. Achard et al. (L3 Collaboration), Phys. Lett. B 561, 202 (2003); Eur. Phys. J. C 45, 569 (2006); G. Abbiendi et al. (OPAL Collaboration), 45, 291 (2006); OPAL Collaboration45, 307 (2006); S. Schael et al. (ALEPH Collaboration), 47, 309 (2006); ALEPH Collaboration48, 685 (2006); J. Abdallah et al. (DELPHI Collaboration), 51, 249 (2007); 55, 1 (2008).
  9. A. Barbaro-Galtieri, F. Margaroli, and I. Volobouev, Rep. Prog. Phys. 75, 056201 (2012).
  10. P. Z. Skands, arXiv:0905.3418.
  11. G. Aad et al. (ATLAS Collaboration), arXiv:1203.4211.
  12. S. Chatrchyan et al. (CMS Collaboration), Phys. Lett. B 709, 28 (2012).
  13. CMS Collaboration, Public Note No. PAS TOP-11-030, 2012.
  14. J. H. Kühn and G. Rodrigo, in Ref. [4].
  15. T. M. Liss and A. Quadt, mini-review on the top quark, in K. Nakamura et al. (Particle Data Group), J. Phys. G 37, 075021 (2010), p. 596.
  16. Y. Nambu, in Preludes in Theoretical Physics, edited by A. De-Shalit, H. Feshbach, and L. Van Hove (North-Holland, Amsterdam, 1966), p. 133.
  17. H. J. Lipkin, Phys. Lett. 45B, 267 (1973).
  18. For a simple prescription for evaluating the corresponding group-theoretic factors, see J. L. Rosner, in Techniques and Concepts of High-Energy Physics, edited by T. Ferbel, NATO Advanced Study Institutes Series B: Physics, Vol. 66 (Plenum, New York, 1981), pp. 112–114.
  19. Y. Nambu, Phys. Rev. D 10, 4262 (1974).
  20. For an elementary discussion see J. L. Rosner in [18], pp. 18–20.
  21. J. L. Rosner, Phys. Lett. B 385, 293 (1996).
  22. X. Artru and G. Mennessier, Nucl. Phys. B70, 93 (1974).
  23. B. Andersson, G. Gustafson, G. Ingelman, and T. Sjostrand, Phys. Rep. 97, 31 (1983).
  24. CMS Collaboration, arXiv:1205.0594.
  25. P. Z. Skands, B. R. Webber, and J. Winter, arXiv:1205.1466.
  26. S. J. Brodsky and X.-G. Wu, Phys. Rev. D 85, 114040 (2012).

Outline

Information

Phys. Rev. D 86, 014011– Published 11 July, 2012
  • Received 14 May 2012
Article part of CHORUS

© 2012 American Physical Society

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation