相关论文: One-loop QCD Corrections to Top Quark Decay into a…
We calculate the full electroweak one-loop corrections to the decay of the CP-odd Higgs boson A^0 into scalar quarks in the minimal supersymmetric extension of the Standard Model (MSSM). Due to the complex structure of the electroweak…
We present analytic results for the one-loop corrections of the helicity amplitudes of the QCD five-parton subprocesses involving four quarks and one gluon obtained with a standard Feynman diagram calculation using dimensional reduction.
The low-lying energy excitations of 2-flavour QCD in the chiral limit confined to a small spatial box ($\delta$-regime) are that of an $O(4)$ rotator. In this work, we calculate the corrections due to the presence of a nonzero quark mass up…
We evaluate the three-loop corrections to the matching coefficient of the vector current between Quantum Chromodynamics (QCD) and non-relativistic QCD. The result is presented in the MSbar scheme where large perturbative corrections are…
We improve the precision of the topological susceptibility of QCD, and therefore of the QCD axion mass, by including $O(\alpha_{\rm em})$ and NNLO corrections in the chiral expansion, which amount to 0.65(21)% and -0.71(29)% respectively.…
We present a fully differential next-to-next-to-leading order calculation of t-channel single top-quark production and decay at the LHC under narrow-width approximation and neglecting cross-talk between incoming protons. We focus on the…
We report on our current progress in the study of finite one-loop radiative corrections in the minimal Lorentz- and CPT-violating QED extension.
The preceding experimental and theoretical results on the rare decay $\pi^0 \to e^+e^-$ are briefly summarized. Already computed two-loop QED corrections are reviewed and the bremsstrahlung contribution beyond the soft-photon approximation…
We compute the two-loop QCD corrections to $q g \to H q$ and $q \bar{q} \to H g$ amplitudes mediated by loops of nearly massless quarks. These amplitudes provide the last missing ingredient required to compute the NLO QCD corrections to the…
Using a Generic spin basis, we present a general formalism of one-loop radiative corrections to the spin correlations in the top quark pair production at the Next Linear Collider, and calculate the O(\alpha_s) QCD corrections under the soft…
The extracted value of the relic density has reached the few per-cent level precision. One can therefore no longer content oneself with calculations of this observable where the annihilation processes are computed at tree-level, especially…
We study the rare decay $Z_H \rightarrow H^0 \gamma$ at $\mathcal{O}(\alpha_{{\rm ew}}^{3}\alpha_s)$ accuracy including two-loop QCD corrections in the context of the littlest Higgs model (LHM) without $T$-parity. We revisit analytically…
We present the virtual corrections due to the top-quark loops for the process $gg \to ZZ$ at next-to-leading order in QCD. The associated two-loop box diagrams are computed using a small-transverse-momentum expansion. Our results are then…
We present a calculation for the $K^+\to\pi^+ \pi^0 $ decay amplitude using a quenched simulation of lattice QCD with the Wilson quark action at $\beta=6/g^2=6.1$. The decay amplitude is extracted from the ratio, the $K\to\pi\pi$…
The decay B_s -> mu^+ mu^- in the Standard Model is generated by the well-known W-box and Z-penguin diagrams that give rise to an effective quark-lepton operator Q_A at low energies. We compute QCD corrections of order alpha_s^2 to its…
We discuss the results for the four-top quark production process at the LHC at NLO accuracy in perturbative QCD for the $3\ell$ decay channel. The QCD corrections are applied in both the production and the decay stages of the four top…
We present a computation of QCD next-to-leading order virtual corrections to the top production and decay process at linear colliders. The top quarks are allowed to be off-shell and the production and decay subprocesses are treated…
We consider the field equations of a static magnetic field including one-loop QED corrections, and calculate the corrections to the field of a magnetic dipole. PACS: 12.20.Ds, 97.60.Jd, 97.60.Gb
We report on our computation of the mixed QCD and weak corrections to $q {\bar q} \to t\bar{t}$ including $t, \bar t$ spin effects, in particular on single top spin asymmetries.
We present the result for the three-loop singlet QCD corrections to the decay of a Higgs boson into two photons and improve the calculation for the non-singlet case. With the new result presented, the decay width Gamma(H -> \gamma \gamma)…