Skip to main content
Log in

A precise measurement of the B + , B0 and mean b-hadron lifetime with the DELPHI detector at LEP I

  • experimental physics
  • Published:
The European Physical Journal C - Particles and Fields Aims and scope Submit manuscript

Abstract.

Final results from the DELPHI Collaboration on the lifetime of B + and B0 mesons and the mean b-hadron lifetime, are presented using the data collected at the Z 0 peak in 1994 and 1995. Elaborate, inclusive, secondary vertexing methods have been employed to ensure a b-hadron reconstruction with good efficiency. To separate samples of B + and B0 mesons, high performance neural network techniques are used that achieve very high purity signals. The results obtained are: \( \tau_{\mathrm B}^ + = 1.624 \pm 0.014\;\;(stat) \pm 0.018\; (syst) ps \) \( \tau_{\mathrm B}^0\quad = 1.531 \pm 0.021 \;\;(stat)\pm 0.031 \; (syst) ps \) \( \frac{\tau_{{\mathrm B}^ + }}{\tau_{{\mathrm B}^0}} = 1.060 \pm 0.021 \;\;(stat)\pm 0.024\;(syst) \) and for the average b-hadron lifetime: \( \tau_{{\mathrm b}} = 1.570 \pm 0.005\;\;(stat) \pm 0.008 \; (syst) ps. \)

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. I.I. Bigi et al., in: B Decays 2nd edition, edited by S. Stone, World Scientific (1994); A. Lenz, talk given at the Workshop on the CKM Unitarity Triangle, CERN, Feb. 13th-16th 2002, http://ckm-workshop.web.cern.ch/ckm-workshop and hep-ph/0304132/

  2. K. Hagiwara et al., Phys. Rev. D 66, 010001 (2002) and 2003 off-year partial update for the 2004 edition available on the PDG WWW pages (URL: http://pdg.lbl.gov/)

    Article  Google Scholar 

  3. Z. Albrecht, T. Allmendinger, G. Barker, M. Feindt, C. Haag, M. Moch, BSAURUS - A package for inclusive B-reconstruction in DELPHI , hep-ex/0102001

  4. DELPHI Collaboration, P. Aarnio et al., Nucl. Instr. Methods A 303, 233 (1991)

    Google Scholar 

  5. DELPHI Collaboration, P. Abreu et al., Nucl. Instr. Methods A 378, 57 (1996)

    Google Scholar 

  6. V. Chabaud et al., Nucl. Inst. Meth A 368, 314 (1996)

    Google Scholar 

  7. DELPHI Collaboration, J. Abdallah et al., CERN-EP/2002-088 (submitted to Eur. Phys. J. C)

  8. T. Sjöstrand, Comp. Phys. Commun. 82, 74 (1994)

    Article  Google Scholar 

  9. DELPHI Collaboration, P. Abreu et al., Z. Phys. C 73, 11 (1996)

    Article  Google Scholar 

  10. DELPHI Collaboration, P. Abreu et al., Phys. Lett. B 475, 429 (2000)

    Article  Google Scholar 

  11. Z. Albrecht, M. Feindt, M. Moch, MACRIB, high efficiency, high purity hadron identification for DELPHI, hep-ex/0111081

  12. K. Harder, in: Proceedings of the 31st International Conference on High Energy Physics, ICHEP 2002, Amsterdam, edited by S. Bentvelsen, P. de Jong, J. Koch and E. Laenen (Elsevier Science BV), pp. 535-538

  13. Results prepared by the LEP B Lifetime Working Group and the Working Group on B Oscillations for the XXXVIth Recontres de Moriond, Les Arcs, March 2001

  14. MARK III Collaboration, D. Coffman et al., Phys. Lett. B 263, 135 (1991)

    Article  Google Scholar 

  15. ALEPH, CDF, DELPHI, L3,OPAL, SLD, Combined results on b-hadron production rates and decay properties, CERN-EP/2001-050

  16. DELPHI Collaboration, P. Abreu et al., Z. Phys. C 68, 13 (1995)

    Google Scholar 

  17. DELPHI Collaboration, P. Abreu et al., Z. Phys. C 74, 19 (1997)

    Article  Google Scholar 

  18. DELPHI Collaboration, W. Adam et al., Z. Phys. C 68, 363 (1995)

    Google Scholar 

  19. OPAL Collaboration, G. Abbiendi et al., Phys.Lett. B 493, 266 (2000)

    Article  Google Scholar 

  20. BABAR Collaboration, B. Aubert et al., Phys. Rev. Lett. 89, 061801 (2002)

    Article  Google Scholar 

  21. BELLE Collaboration, K. Abe et al., BELLE Collaboration, Phys. Rev. Lett. 88, 0171801 (2002)

    Article  Google Scholar 

  22. R. Barate et al., ALEPH Collab., Phys. Lett. B 492, 275 (2000)

    Article  Google Scholar 

  23. D. Buskulic et al., ALEPH Collab., Z. Phys. C 71, 31 (1996)

    Article  Google Scholar 

  24. F. Abe et al., CDF Collab., Phys. Rev. D 58, 092002 (1998)

    Article  Google Scholar 

  25. D. Acosta et al., CDF Collab., Phys. Rev. D65, (2003) 092009

  26. M. Acciari et al., L3 Collab., Phys. Rev. Lett. B 438, 417 (1998)

    Article  Google Scholar 

  27. R.Akers et al., OPAL Collab., Z. Phys. C 67, 379 (1995)

    Google Scholar 

  28. G. Abbiendi et al., OPAL Collab., Eur. Phys. J. C12 (2000) 609-626

  29. K. Abe et al., SLD Collab., Phys. Rev. Lett. 79, 590 (1997)

    Article  Google Scholar 

  30. B. Aubert et al., BABAR Collab., Phys. Rev. Lett. 87, 201803 (2001)

    Article  Google Scholar 

  31. B. Auber et al., BABAR Collab., Phys. Rev. D, hep-ex/0212017, to be published

  32. M. Acciarri et al., L3 Collab., Phys. Lett. B 416, 220 (1998)

    Article  Google Scholar 

  33. DELPHI Collaboration, P. Abreu et al., Phys.Lett. B 377, 195 (1996)

    Article  Google Scholar 

Download references

Author information

Consortia

Additional information

Received: 6 October 2003, Revised: 12 December 2003, Published online: 25 February 2004

Rights and permissions

Reprints and permissions

About this article

Cite this article

The DELPHI Collaboration. A precise measurement of the B + , B0 and mean b-hadron lifetime with the DELPHI detector at LEP I. Eur. Phys. J. C 33, 307–324 (2004). https://doi.org/10.1140/epjc/s2004-01599-5

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1140/epjc/s2004-01599-5

Keywords

Navigation