English

Experimental determination of the b quark mass in DELPHI

High Energy Physics - Experiment 2011-01-27 v1

Abstract

The running mass of the b quark as defined in the MS-bar renormalization scheme, m_b, was measured at the M_Z scale using 2.8 million hadronic Z^0 decays collected by the DELPHI experiment at LEP. The result is m_b(M_Z) = 2.67 +- 0.25 (stat.) +- 0.34 (frag.) +- 0.27(theo.) GeV/c^2 which differs from that obtained at the Upsilon scale, by m_b(M_\Upsilon/2)-m_b(M_Z) = 1.49 +- 0.52 GeV/c^2. This measurement, performed far from the bbˉb\bar{b} production threshold, provides the first experimental observation of the running of the quark masses.

Keywords

Cite

@article{arxiv.hep-ex/9708030,
  title  = {Experimental determination of the b quark mass in DELPHI},
  author = {S. Marti i Garcia and J. Fuster and S. cabrera},
  journal= {arXiv preprint arXiv:hep-ex/9708030},
  year   = {2011}
}

Comments

Talk given at the QCD 97 conference held in Montpellier, July 1997. Also available here http://hep.ph.liv.ac.uk/~martis/