A summary of recent ATLAS results on top pair production, both differential and associated production.
Recent advances in machine learning have made it possible for convolutional neural networks to be applied to classifying boosted jets as either signal (be that tops, Ws or Higgses) or QCD background. These techniques have shown comparable and even superior performance to QCD-based taggers, although have typically relied on constructing 2D ‘images’ of the jets. In this talk, I discuss a new,...
Many theories beyond the Standard Model predict new phenomena which decay to energetic top quarks. Searches for such new physics models are performed using the ATLAS experiment at the LHC using proton-proton collision data collected in 2015 and 2016 with a center-of-mass energy of 13 TeV. Selected recent results will be discussed.
Measurements of single top-quark production in proton-proton collisions are presented based on the 13 TeV and 8 TeV ATLAS datasets. In the leading order process, a $W$-boson is exchanged in the t-channel. The cross-section for the production of single top-quarks and single antitop-quarks, their ratio, as well as differential cross-section measurements are also reported. Measurements of the...
We present progress on our calculation of next-to-leading order QCD effects in single top production for a precision determination of the Wtb coupling. The calculation is performed analytically including an off-shell top quark and includes relevant operators from the Standard Model Effective Field Theory (SMEFT) that modify the Wtb coupling. We discuss the phenomenological importance and put...
We study the effect of multiple soft gluon radiation on the kinematical distributions of the $t$-channel single top quark production at the LHC. By applying the transverse momentum dependent factorization formalism, large logarithms (of the ratio of large invariant mass Q and small total transverse momentum $q_\perp$ of the single-top plus one-jet final state system) are resummed to all orders...
We consider a TeV vector like Top Partner that is a color triplet and electroweak singlet. We study the pair production of the Top Partner at the LHC and its radiative decay modes into SM top and gloun or SM top and photon. The interaction Lagrangian of the Top Partner with SM top is introduce as an effective dimension 5 operator. We focus on the semileptonic final states and use Boosted...
