相关论文: Non-resonant and offshell effects in top-pair obse…
The polarization of a top quark can be sensitive to new physics beyond the standard model. Since the charged lepton from top quark decay is maximally correlated with the top quark spin, it is common to measure the polarization from the…
A previous calculation of electroweak O(alpha) corrections to deep-inelastic neutrino scattering, as e.g. measured by NuTeV and NOMAD, is supplemented by higher-order effects. In detail, we take into account universal two-loop effects from…
The production of a top-quark pair, the heaviest known elementary particle, in association with a light jet is a key process for studying the properties of the Standard Model of Particle Physics. Due to its significance as a signal process…
It is shown that off-forward parton distributions for $\zeta =0$, i.e. where the initial and final state differ only in their transverse momenta, can be interpreted as a simultaneous measurement of the longitudinal momentum and transverse…
We present the implementation of a next-to-leading-order plus parton-shower event generator for the hadronic production of a heavy charm quark accompanied by a leptonically-decaying $W$ boson in the POWHEG BOX RES framework. We consider…
Non-decoupling effects of heavy particles present in beyond-the-standard models are studied for the triple gauge boson vertices $\gamma W^+W^-$ and $Z^0W^+W^-$. We show from a general argument that the non-decoupling effects are described…
We present the calculation of the complete NLO corrections to the off-shell top-quark pair production in the $\ell+j$ decay channel, denoted as $pp \to \ell^- \bar{\nu}_l\, j_b j_b \,jj + X$, where $\ell^- = e^-,\, \mu^-$. The calculation…
We present differential cross sections for the production of top-quark pairs in conjunction with up to two jets, computed at next-to leading order in perturbative QCD and consistently merged with a parton shower in the Sherpa+OpenLoops…
We present a new piece of evidence in favour of the importance of the quark off-shellness in the kaon. The matrix elements of the flavour-changing operators for $K_{L}\to\gamma\gamma$ comply with the general behaviour of the matrix elements…
We demonstrate that the use of analytical on-shell methods involving calculation of the discontinuity across the t-channel cut associated with the exchange of a pair of massless particles (photons or gravitons) can be used to evaluate…
The study of long-range effects arising from the higher order exchange of massless particles via summation of Feynman diagrams is well known, but recently it has been shown that the use of on-shell methods can provide a streamlined route to…
We study the electromagnetic form factors of a nucleon in next-to-leading order chiral perturbation theory (CPT) in the case where one of the nucleons is off its mass shell. We calculate the leading nonanalytic contributions to relevant…
We study the determination of the top-quark mass using leptonic observables in t-channel single top-quark production at the LHC. We demonstrate sensitivity of transverse momentum of the charged lepton on the input top-quark mass. We present…
In this talk we discuss top-quark pair production in association with an additional jet. We present numerical results based on a next-to-leading order QCD calculation.
Analytic expression for energy and angular dependence of a secondary charged lepton in the decay of a polarized top quark with anomalous $tWb$ couplings in the presence of all anomalous couplings are derived. The angular distribution of the…
We review recent results on next-to-leading order (NLO) QCD and electroweak (EW) corrections for processes involving off-shell top quarks. For the off-shell production of two top quarks that decay leptonically, the full NLO EW corrections…
Transverse momentum dependent parton distribution functions are a key ingredient in the description of spin and azimuthal asymmetries in deep-inelastic scattering processes. Recent results from non-perturbative calculations in effective…
Presented here is a technique of propagating uncertainties through the parton shower by means of an alternate event weight. This technique provides a mechanism to systematically quantify the effect of variations of certain components of the…
In this publication, uncertainties in and differences between the MC@NLO and POWHEG methods for matching next-to-leading order QCD calculations with parton showers are discussed. Implementations of both algorithms within the event generator…
The factorization scale dependence of the anomalous top-Higgs coupling effects in the leading order differential cross sections and distributions of the secondary lepton in the process of associated production of the top quark pair and the…