CE1: Measurement of the t quark mass
LHC copiously produces t quarks. This allows for many high precision measurements which currently are statistically limited due to the small number of produced and reconstructed t quarks at the Tevatron (Fermilab, FNAL). In any case the mass of the t quark is a particularly relevant parameter since it allows for a consistency check of the standard model if combined with the mass of the W boson. Recent measurements show a small but not yet significant inconsistency indicating that the standard model expects a Higgs boson mass in a mass range which is already excluded by the negative results of direct searches [1]. In order to obtain significant measurements of the t quark mass despite the small available statistics, an approach call matrix element method has been established and developed in this research training school [2]. It has been successfully applied for measuring the t quark mass [3] at the Tevatron. The experience from using the matrix element method at the DØ experiment at the Tevatron should be transferred to the ATLAS experiment at LHC in order to establish this matrix element approach also there.
References:
LHC copiously produces t quarks. This allows for many high precision measurements which currently are statistically limited due to the small number of produced and reconstructed t quarks at the Tevatron (Fermilab, FNAL). In any case the mass of the t quark is a particularly relevant parameter since it allows for a consistency check of the standard model if combined with the mass of the W boson. Recent measurements show a small but not yet significant inconsistency indicating that the standard model expects a Higgs boson mass in a mass range which is already excluded by the negative results of direct searches [1]. In order to obtain significant measurements of the t quark mass despite the small available statistics, an approach call matrix element method has been established and developed in this research training school [2]. It has been successfully applied for measuring the t quark mass [3] at the Tevatron. The experience from using the matrix element method at the DØ experiment at the Tevatron should be transferred to the ATLAS experiment at LHC in order to establish this matrix element approach also there.
References:
- S. Heinemeyer,
Electroweak Precision Physics from Low to High Energy,
Plenary talk at 23rd International Symposium on Lepton-Photon Interactions at High Energy (LP07), Daegu, Korea, 13-18 Aug 2007, http://chep.knu.ac.kr/lp07/htm/S1/S01_3.pdf, arXiv:0710.3022 [hep-ph] - F. Fiedler,
Independent measurement of the top quark mass and the light- and bottom-jet energy scales at hadron colliders,
Eur. Phys. J. C53 (2008) 41, arXiv:0706.1640 [hep-ex] - V. M. Abazov et al. [DØ Collaboration],
Measurement of the top quark mass in the lepton + jets final state with the matrix element method,
Phys. Rev. D74 (2006) 092005, hep-ex/0609053.
