Related papers: NNLO tau+tau- production cross section at threshol…
Recent developments in the treatment of a system of heavy quarks close to their production threshold are discussed. Particular emphasis is put on the next-to-next-to-next-to-leading order (N$^3$LO) corrections to the energy levels and the…
One of the most challenging open problems in heavy quarkonium physics is the double charm production in $e^+e^-$ annihilation at B factories. The measured cross section of $e^+ e^- \to J/\psi + \eta_c$ is much larger than leading order (LO)…
We present new results on the NNNLO top-antitop production cross section near threshold from potential and ultrasoft gluon corrections. The new non-logarithmic third-order terms are in the 10% range and lead to a significant reduction in…
It was reported that the NNLO correction to the total cross section near the ttbar threshold in e+e- collisions is as large as the NLO correction to it. In the thesis, we improve the convergence of the perturbative series of the total cross…
We perform a complete calculation of the next-to-next-to-leading order (NNLO) electroweak fermionic corrections to fermion-pair production processes, where "fermionic" refers to contributions with closed fermion loops. We did this via a…
The cross sections for the reaction $e^+ e^- \rightarrow l \bar l q \bar q $ and for similar four fermion production processes at LEP~1, LEP~2 and the NLC are calculated. Due to the extraordinary symmetry properties of the process, very…
We compute the next-to-next-to-leading order (NNLO) QCD correction to the total cross-section for the reaction gg \to t\bar t + X. Together with the partonic channels we computed previously, the result derived in this letter completes the…
In this paper, we calculate the next-to-next-to-leading-order (NNLO) QCD corrections to $e^+e^- \to J/\psi+\eta_c$ at the $B$ factories. After including the NNLO corrections, the cross section of $e^+e^- \to J/\psi+\eta_c$ is enhanced by…
We calculate the complete next-to-leading-order (NLO) QCD corrections (including SUSY QCD corrections) to the inclusive total cross sections of the associated production processes $pp\rightarrow A^{0}\gamma+X$ in the minimal supersymmetric…
Several aspects of next-to-leading (NLO) order corrections to see-saw formulas are discussed and phenomenologically relevant situations are identified. We generalize the formalism to calculate the NLO terms developed for the type I see-saw…
In this paper we present a next-to-next-to-leading order (NNLO) QCD calculation of the processes $pp\rightarrow l^+l^-\gamma$ and $pp\rightarrow \nu\bar\nu\gamma$ that we have implemented in MCFM. Our calculation includes QCD corrections at…
We analyse the subleading non-resonant contributions to the e+ e- -> W+ W- b bbar cross section at energies near the top-antitop threshold. These correspond to next-to-next-to-leading-order (NNLO) corrections with respect to the…
We determine the NNLO electroweak correction to the $e^+ e^-\to b\bar{b}W^+W^- X$ production cross section near the top-pair production threshold. The calculation includes non-resonant production of the final state as well as electroweak…
I present a calculation of next-to-next-to-next-to-leading-order (NNNLO) soft-gluon corrections for top-antitop pair production in hadronic collisions. Approximate NNNLO (aNNNLO) results are obtained by adding the NNNLO soft-gluon…
The total cross section of the top quark-antiquark pair production near threshold in $\gamma\gamma$ collision is computed analytically up to the next-to-leading order in perturbative and nonrelativistic expansion for general photon…
We determine the next-to-leading logarithmic (NLL) QCD corrections to the cross section sigma(e+e- to t bar t H) for center-of-mass energies up to 500 GeV. The dynamics is dominated by nonrelativistic effects, and the summation of terms…
In heavy quarkonium production, the measured ratio $R_{c \bar c}=\sigma[J/\psi+ c\bar c + X]/\sigma[J/\psi +X]$ at B factories is much larger than existing theoretical predictions. To clarify this discrepancy, in nonrelativistic QCD (NRQCD)…
We extend previous work on applying the epsilon-expansion to universal properties of a cold, dilute Fermi gas in the unitary regime of infinite scattering length. We compute the ratio xi = mu/epsilon_F of chemical potential to ideal gas…
We derive high-order threshold corrections for top quark production in hadronic collisions from resummation calculations. We present analytical expressions for the cross section through next-to-next-to-next-to-next-to-leading order (N^4LO)…
We present an analytical description of top-antitop pair production near the threshold in $e^+e^-$ annihilation and $\g\g$ collisions. A set of basic observables considered includes the total cross sections, forward-backward asymmetry and…