相关论文: Top Decay and Bottom Fragmentation in NLO QCD

We present a calculation of the next-to-leading order QCD corrections, with one-scale phase space slicing method, to single top quark production and decay process $p\bar{p},pp\to t\bar{b}+X\to b\ell\nu\bar{b}+X$ at hadron colliders. Using…

Motivated by ongoing new physics searches in the top-quark sector at the Large Hadron Collider we report on the calculation of NLO QCD corrections to the Standard Model $pp\to t\bar{t}Z+X$ process in the tetra-lepton decay channel. This…

We study the inclusive production of hadrons with bottom flavor at the LHC and its luminosity upgrade. We describe the collinear fragmentation of singly $b$-flavored hadrons, $B$ mesons and $\Lambda_b$ baryons, via the KKSS07 determination…

We present a detailed analysis of the use of heavy quark fragmentation into heavy hadrons for testing the heavy quark effective theory through comparison of the measured fragmentation parameters of the $c$ and $b$ quarks. Our analysis is…

The nonleptonic two-body $B^{\ast}$ ${\to}$ $\bar{D}D$ weak decays are studied phenomenologically with the perturbative QCD factorization approach. It is found that the $B_{s}^{{\ast}0}$ ${\to}$ $D_{s}^{-}D_{s}^{+}$, $B_{d}^{{\ast}0}$…

The perturbative QCD approach is based on $k_T$ factorization, including the Sudakov form factors so that to avoid the endpoint singularity. In this approach, we calculate the charmless B decays like $B\to \pi\pi$ decays etc. to produce the…

We present nonperturbative fragmentation functions (FFs) for bottom-flavored ($B$) hadrons both at next-to-leading (NLO) and, for the first time, at next-to-next-to-leading order (NNLO) in the $\overline{\mathrm{MS}}$ factorization scheme…

Distributions of charged leptons in semileptonic $\Lambda_c$ and $\Lambda_b$ decays can be used as spin analysers for the corresponding charm and bottom quarks. QCD corrections to the energy spectra of charged leptons have been given in the…

Higher-order QED radiative corrections to muon decay spectrum are evaluated within the QED structure function approach in the next-to-leading order logarithmic approximation. New analytical results are given in the…

Analytic formulae are given for QCD corrections to the lepton spectra in decays of polarised up and down type heavy quarks. These formulae are much simpler than the published ones for the corrections to the spectra of charged leptons…

We consider QCD radiative corrections to top-quark pair production at hadron colliders. We use the $q_T$ subtraction formalism to perform a fully-differential computation for this process. Our calculation is accurate up to the…

We calculate the leading perturbative and power corrections to the hadronic invariant mass and energy spectra in semileptonic heavy hadron decays. We apply our results to the $B$ system. Moments of the invariant mass spectrum, which vanish…

We present predictions for $t \bar t$ and $t \bar t H$ production and decay at future lepton colliders including non-resonant and interference contributions up to next-to-leading order (NLO) in perturbative QCD. The obtained precision…

The gluon emission from an energetic heavy quark is suppressed in the forward direction below the angle $\Theta\lesssim m_Q/E$ for a quark of mass $m_Q$ and energy $E$ according to perturbative Quantum Chromodynamics (QCD) (``dead cone").…

We study bottom-quark fragmentation in e+e- annihilation, top and Higgs decay H -> b bbar, using Monte Carlo event generators, as well as calculations, based on the formalism of perturbative fragmentation functions, which resum soft- and…

The complete set of matrix elements for all polarization configurations in top quark decays is presented including higher order QCD corrections. The analysis is done in the framework of the helicity formalism. The results can be used in a…

We present our analytic results for the NLO corrections to the partial decay width $t\to H^+b$ followed by $b\to BX$ for nonzero b-quark mass ($m_b\neq 0$) in the Fixed-Flavor-Number scheme (FFNs). To make our predictions for the energy…

We compute the hadronic production of top-antitop pairs in association with a Higgs boson at next-to-leading-order QCD, including the decay of the top and antitop quark into bottom quarks and leptons. Our computation is based on full…

We report on the first fully differential calculation of the next-to-next-to-leading-order (NNLO) QCD radiative corrections to the production of bottom-quark pairs at hadron colliders. The calculation is performed by using the $q_T$…

The production of top-quark pairs that subsequently decay hadronically and leptonically (lepton+jets channel) is one of the key processes for the study of top-quark properties at the LHC. In this article, NLO QCD corrections of order…