相关论文: Effective field theory approach to top-quark decay…

We discuss new physics in top-quark interactions, using an effective field theory approach. We consider top-quark decay, single top production, and top-quark pair production. We identify 15 dimension-six operators that contribute to these…

The top quark is expected to be a probe to new physics beyond the standard model. Thanks to the large number of top quarks produced at the Tevatron and the LHC, various properties of the top quark can now be measured accurately. An…

We adopt a fully gauge-invariant effective-field-theory approach for parametrizing top-quark flavor-changing-neutral-current interactions. It allows for a global interpretation of experimental constraints (or measurements) and the…

Computations at next-to-leading order in the Standard Model offer new technical challenges in presence of higher dimensional operators. We introduce a framework that, starting from the top-quark effective field theory at dimension six,…

We present an effective-field-theory calculation of the effect of a dimension-six operator involving the top quark on precision electroweak data via a top-quark loop. We demonstrate the renormalizability, in the modern sense, of the…

We review some recent theoretical progresses towards the determination of the top-quark couplings beyond the standard model. We briefly introduce the global effective field theory approach to the top-quark production and decay processes,…

We present the complete calculation of the top-quark decay width at next-to-next-to-leading order in QCD, including next-to-leading electroweak corrections as well as finite bottom quark mass and $W$ boson width effects. In particular, we…

We compute the branching ratios for the rare top quark decays t to c gamma and t to c Z mediated by effective flavor changing neutral couplings at the next-to-leading order in QCD including the effects due to operator mixing. After…

We consider top quark decay in the Standard Model Effective Field Theory (SMEFT). We present a calculation of the total decay width and the $W$-boson helicity fractions at next-to-leading order (NLO) in SMEFT. Our result includes the…

I report on recent developments in the heavy-quark effective theory and its application to $B$ meson decays. The parameters of the effective theory, the spin-flavor symmetry limit, and the leading symmetry-breaking corrections to it are…

Neutral flavor-changing transitions are hugely suppressed in the Standard Model and therefore they are very sensitive to new physics. We consider the decay rate of t->u_i h where u_i=u,c using an effective field theory approach. We perform…

The imminent start of the Large Hadron Collider, which is expected to produce $\sim 10^8$ $t\bar{t}$ pairs per year, provides an unprecedented opportunity for top physics. As the top quark is widely expected to be rather sensitive to…

Physics beyond the standard model can affect top-quark physics indirectly. We describe the effective field theory approach to describing such physics, and contrast it with the vertex-function approach that has been pursued previously. We…

We develop a new nonrelativistic effective field theory of $\rho$NRQCD [1] to describe the finite lifetime effects in the threshold production of top quark-antiquark pairs. The theory is based on the expansion in a parameter…

We investigate the electromagnetic properties of the fully charm tetraquark states, particularly incorporating contributions from internal gluon radiations. The paper first presents analytical expressions for the next-to-leading-order (NLO)…

After a short introduction to effective field theories, most of their features are illustrated using the top decay. The effects of heavy new physics on the top decay are computed and the constraints on the coefficients of the dimension-six…

We study the pair production of scalar top-quark partners decaying to a top-quark pair plus large missing energy at the LHC, a signature which appears in numerous models that address outstanding problems at the TeV-scale. The severe…

We apply effective field theory techniques to study several heavy quark systems. The topics analysed include the singlet static QCD potential, anomalous dimensions in SCET and a comprehensive study of semi-inclusive radiative heavy…

We describe the application of effective field theories for quantum chromodynamics (QCD) to two bound states involving heavy quarks: the $T_{cc}^+$ exotic meson and the $J/\psi$. We study the decay of the $T_{cc}^+$ in an effective theory…

Analyticity and unitarity constrain certain classe of new physics models by linking flavor-conserving and flavor-violating four-fermion interactions. In this work, we explore how these theoretical relations impact flavor-violating rare top…