Determination of the top quark mass circa 2013: methods, subtleties, perspectives

Abstract

We present an up-to-date overview of the problem of top quark mass determination. We assess the need for precision in the top mass extraction in the LHC era together with the main theoretical and experimental issues arising in precision top mass determination. We collect and document existing results on top mass determination at hadron colliders and map the prospects for future precision top mass determination at e + e − colliders. We present a collection of estimates for the ultimate precision of various methods for top quark mass extraction at the LHC.

Indirect determinations of the top quark mass

“…We estimate the following future top mass uncertainties 17) in good agreement with our numerical results in figure 4.…”

“…These measurements are compared to the results of theoretical calculations, which are expressed in terms of M t in a well-defined renormalisation scheme. In the context of hadron colliders, the extraction of M t suffers from a variety of effects linked to hadronization that are not fully accountable by perturbative QCD calculations, like bound-state effects of the tt pairs, parton showering, and other non-perturbative corrections (see [17,18] for a thorough discussion). In practice, the extraction of M t relies on modelling based on Monte-Carlo generators, and this is why [19] refers to M t in eq.…”

Z ′, Higgses and heavy neutrinos in U(1)′ models: from the LHC to the GUT scale

“…Due to its origin, the measurement leads to the so-called MC mass which does represent neither the pole mass nor the MS mass. Usually, one assumes that the MC mass is sufficiently close to the pole mass with differences estimated of the order of 1 GeV [58][59][60] and then extracts its MS value using matching conditions at the EW scale. The corresponding Yukawa coupling Y t is then determined and fed to the RG equations.…”

Top physics at the LHC

“…As both the 1S mass and the MS mass are short-distance masses, the relation between them is O(Λ 2 QCD /m) [60]. At lepton colliders, it might be feasible to determine the 1S top mass with a precision of about 100 MeV [62] (see this reference also for an overview of other methods). Another promising short-distance mass is the potential-subtracted mass [63], which employs the fact that the IR sensitive part of the pole, discussed in section 2.3 cancels against the IR sensitivity of the top-antitop Coulomb potential in threshold production.…”