arXiv subjects
Publications and source records attributed to Richard Hawkings.
A review of ATLAS and CMS measurements of the inclusive $t\bar{t}$ production cross-section in $pp$ collisions at $\sqrt{s}=$7-13 TeV is presented, focusing on the most precise results in the dilepton and lepton+jets final states. The measurements are in good agreement with state-of-the-art QCD predictions, and have been used to determine the top quark pole mass and provide constraints on proton parton distribution functions.
Top quark physics measurements performed using data from the ATLAS detector at the LHC rely on efficient reconstruction and precise calibration of leptons, jets and missing transverse energy. A review of the techniques used to reconstruct such objects is given, with an emphasis on the uncertainties achieved for energy calibration and efficiency measurements, illustrated with their impact on key top quark physics results.
Measurements of top quark properties performed at the Large Hadron Collider are reviewed, with a particular emphasis on top-pair charge asymmetries, spin correlations and polarization measurements performed by the ATLAS and CMS collaborations. The measurements are generally in good agreement with predictions from next-to-leading-order QCD calculations, and no deviations from Standard Model expectations have been seen.
This note describes a study of the possibilities for selecting an electron calibration stream using the High level electron trigger (Level 2 and the event filter). Using the electromagnetic calorimeter reconstruction and the track reconstruction algorithms, an evaluation has been performed of the selection efficiencies and purities for different physics channels with single or double electrons in the final state. A study of the calibration stream composition, including the background from QCD processes, is presented.
B physics results from e+ e- annihilation at the Z0 resonance are reviewed. A vast program is summarised, including the study of B+, B0d, B0s and b baryon lifetimes, the time dependence of B0d and B0s oscillations, the width difference in the B0s system, and the measurements of the magnitudes of the CKM matrix elements Vcb and Vub.
A future linear collider such as TESLA may be able to run on the Z0 resonance with very high luminosity and polarised electron and positron beams. The possibilities of measuring electroweak quantities with high precision are investigated. Huge improvements with respect to the present precision can be expected, especially for the asymmetries A_LR and A_b where beam polarisation can be exploited. The very large sample of Z to bbbar events also allows studies of various CP-violating b decays. The precision achievable on the CKM unitarity triangle angles is comparable to experiments at b factories and future hadron colliders.