Abstract.
The standard method used for tagging b-hadrons in the DELPHI experiment at the CERN LEP Collider is discussed in detail. The main ingredient of b-tagging is the impact parameters of tracks, which relies mostly on the vertex detector. Additional information, such as the mass of particles associated to a secondary vertex, significantly improves the selection efficiency and the background suppression. The paper describes various discriminating variables used for the tagging and the procedure of their combination. In addition, applications of b-tagging to some physics analyses, which depend crucially on the performance and reliability of b-tagging, are described briefly.
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References
N. Bingefors, Nucl. Instr. and Meth. A328 (1993) 447.
V. Chabaud, Nucl. Instr. and Meth. A368 (1996) 314.
P. Chochula, Nucl. Instr. and Meth. A412 (1998) 304.
A. Andreazza, Nucl. Instr. and Meth. A367 (1995) 198
P.Collins, The Alignment and Performance of the DELPHI Double-Sided Vertex Detector, Proceedings of the fourth International Workshop on Vertex Detectors, June 1995, Ein Gedi Resort, Dead Sea, Israel, p. 13.
ALEPH Collaboration, Phys. Lett. B 313, 535 (1993).
DELPHI Collaboration, Nucl. Instr. and Meth. A 378, 57 (1996).
DELSIM reference Manual, DELPHI 87-98 PROG 100, Geneva, 1989
DELANA User’s Guide, DELPHI 89-44 PROG 137, Geneva, 1989
G. Borisov and C. Mariotti, Nucl. Inst. Meth. A 372, 181 (1996).
ALEPH Collaboration, Phys. Lett. B 401, 150 (1997) and 163.
SLD Collaboration, Phys. Rev. Lett. 80, 660 (1998).
G. Borisov, Nucl. Instr. and Meth. A 417, 384 (1998).
DELPHI Collaboration, E. Phys. J. C 10, 415 (1999).
T.W. Anderson, An introduction to multivariate analysis, Wiley, New York, 1958.
T. Sjöstrand, Comp. Phys. Comm. 39, 347 (1986)
DELPHI Collaboration, Z.Phys. C 73, 11 (1996).
A. Ballestrero , Report of the QCD Working Group, hep-ph/0006259
E. Norrbin and T. Sjöstrand, Nucl. Phys. B 603, 297 (2001).
G. Rodrigo, Nucl. Phys. Proc. Suppl. 54A, 60 (1997)
The LEP/SLD Heavy Flavour Working Group, Final input parameters for the LEP/SLD heavy flavour analyses, LEPHF/2001-01
DELPHI Collaboration, Phys. Lett. B 462, 425 (1999).
DELPHI Collaboration, Phys. Lett. B 425, 399 (1998).
S. Catani, Phys. Lett. B 269, 432 (1991)
Yu. L. Dokshitzer, G. D. Leder, S. Moretti and B. R. Webber, JHEP 9708:001 (1997), hep-ph\(/\)9707323.
DELPHI Collaboration, Phys. Lett. B 418, 430 (1998)
DELPHI Collaboration, Phys. Lett. B 499, 23 (2001).
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Received: 14 January 2003, Revised: 14 October 2003, Published online: 3 December 2003
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The DELPHI Collaboration. b-tagging in DELPHI at LEP. Eur. Phys. J. C 32, 185–208 (2004). https://doi.org/10.1140/epjc/s2003-01441-8
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DOI: https://doi.org/10.1140/epjc/s2003-01441-8