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Related papers: Three-loop matching of the vector current

200 papers

The status of the theoretical predictions for the top-anti top production in hadronic collisions is shortly reviewed, paying a articular attention to the analytic calculation of the two-loop QCD corrections to the parton-level matrix…

High Energy Physics - Phenomenology · Physics 2010-12-02 R. Bonciani , A. Ferroglia , T. Gehrmann , A. von Manteuffel , C. Studerus

We compute the three-loop corrections to the quark axial vector form factor in massless QCD, focusing on the pure-singlet contributions where the axial vector current couples to a closed quark loop. Employing the Larin prescription for…

High Energy Physics - Phenomenology · Physics 2021-03-24 T. Gehrmann , A. Primo

We present a concise summary of recent results for the vector correlator in massless QCD at order ${\cal O}(\alpha_s^4)$, with all colour factors being given for a generic colour group. As a direct consequence we arrive at: (i) the full QCD…

High Energy Physics - Phenomenology · Physics 2015-06-05 P. A. Baikov , K. G. Chetyrkin , J. H. Kühn , J. Rittinger

Higgs boson pair production plays an important role in the determination of the Higgs boson self coupling. The predictions based on next-to-leading order corrections show a large dependence on the renormalization scheme of the top quark…

High Energy Physics - Phenomenology · Physics 2024-09-13 Matthias Steinhauser

The static potential between an infinitely heavy quark and antiquark is derived in the framework of perturbative QCD to three loops by performing a full calculation of the two-loop diagrams and using the renormalization group. The…

High Energy Physics - Phenomenology · Physics 2009-10-28 Markus Peter

We compute the two-loop corrections to the helicity amplitudes for the coupling of a massive vector boson to a massless quark-antiquark pair and a gluon, accounting for vector and axial-vector couplings of the vector boson and…

High Energy Physics - Phenomenology · Physics 2023-06-19 Thomas Gehrmann , Tiziano Peraro , Lorenzo Tancredi

We evaluate the two-loop QCD diagrams contributing to the leading color coefficient of the heavy-quark pair production cross section in the gluon fusion channel. We obtain an analytic expression, which is valid for any value of the…

High Energy Physics - Phenomenology · Physics 2011-02-03 R. Bonciani , A. Ferroglia , T. Gehrmann , A. von Manteuffel , C. Studerus

I present one-loop perturbative calculations of matching coefficients between matrix elements in continuum regulated QCD and lattice QCD with overlap fermions, with emphasis a recently-proposed variant discretization of the overlap. These…

High Energy Physics - Lattice · Physics 2016-09-01 Thomas DeGrand

This lecture provides an introduction to quantum chromodynamics (QCD) on the lattice. The continuum limit and Monte Carlo simulations are briefly discussed. Different facets of QCD are nicely exhibited by the potential of a static quark and…

High Energy Physics - Lattice · Physics 2017-06-02 Francesco Knechtli

We compute the three-loop non-singlet corrections to the photon-quark form factors taking into account the full dependence on the virtuality of the photon and the quark mass. We combine the method of differential equations in an effective…

High Energy Physics - Phenomenology · Physics 2022-05-11 Matteo Fael , Fabian Lange , Kay Schoenwald , Matthias Steinhauser

We calculate, to 3 loops in perturbation theory, the bare $\beta$-function of QCD, formulated on the lattice with the clover fermionic action. The dependence of our result on the number of colors $N$, the number of fermionic flavors $N_f$,…

High Energy Physics - Lattice · Physics 2009-11-07 A. Bode , H. Panagopoulos

We present the O(alphas^4) virtual QCD corrections to the scattering process of massless quark qqbar -> gg due to the interference of tree and two-loop amplitudes and to the self-interference of one-loop amplitudes. We work in conventional…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Anastasiou , E. W. N. Glover , C. Oleari , M. E. Tejeda-Yeomans

We study the three-quark static potential in perturbation theory in QCD. A complete next-to-leading order calculation is performed in the singlet, octets and decuplet channels and the potential exponentiation is demonstrated. The mixing of…

High Energy Physics - Phenomenology · Physics 2023-01-13 Nora Brambilla , Jacopo Ghiglieri , Antonio Vairo

We calculate the one loop renormalisation parameters for the heavy-light axial-vector and vector currents using lattice perturbation theory. We use NonRelativistic QCD (NRQCD) heavy quarks and the Highly Improved Staggered Quark (HISQ)…

High Energy Physics - Lattice · Physics 2012-11-28 Christopher Monahan , Christine Davies , Ron Horgan , G. Peter Lepage , Heechang Na , Junko Shigemitsu

We present analytical next-to-leading order results for the correlator of baryonic currents at the three-loop level with one finite mass quark. We obtain the massless and the HQET limits of the correlator as particular cases from the…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Groote , J. G. Körner , A. A. Pivovarov

Using a nonlocal version of the Polyakov-loop-extended Nambu--Jona-Lasinio model, we investi- gate effects of a nonderivative vector-current interaction (relating to the quark-number density) at both real and imaginary chemical potentials.…

High Energy Physics - Phenomenology · Physics 2015-06-12 Thomas Hell , Kouji Kashiwa , Wolfram Weise

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…

High Energy Physics - Phenomenology · Physics 2024-04-24 Giuseppe Degrassi , Ramona Gröber , Marco Vitti

We perform an integral reduction for the 3-loop effective gauge coupling and screening mass of QCD at high temperatures, defined as matching coefficients appearing in the dimensionally reduced effective field theory (EQCD). Expressing both…

High Energy Physics - Phenomenology · Physics 2015-06-05 Jan Moeller , York Schroder

We calculate the next-to-leading order(NLO) quantum chromodynamics(QCD) corrections to the inclusive process of $Z_0 \rightarrow B^*_c+\bar{c}+b$ under the non-relativistic QCD(NRQCD) factorization scheme. Technical details about…

High Energy Physics - Phenomenology · Physics 2015-03-05 Jun Jiang , Long-Bin Chen , Cong-Feng Qiao

We present the two-loop virtual QCD corrections to the scattering of massless distinct quarks in conventional dimensional regularisation. The structure of the infrared divergences agrees with that predicted by Catani while expressions for…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Anastasiou , E. W. N. Glover , C. Oleari , M. E. Tejeda-Yeomans