We report on the first calculation of next-to-next-to-leading order (NNLO) QCD corrections to inclusive production ZZ pairs at hadron colliders. Numerical results are presented for pp collisions with centre-of-mass energy ($\sqrt{s}$) ranging from 7 14 TeV. The NNLO increase NLO result by an amount varying $11\%$ $17\%$ as $\sqrt{s}$ goes loop-induced gluon fusion contribution provides about $60\%$ total effect. When going scale uncertainties do not decrease and remain $\pm 3\%$ level.

Reduze is a computer program for reducing Feynman integrals to master employing variant of Laporta's reduction algorithm. This article describes version 2 the program. New features include distributed single topologies on multiple processor cores. The parallel different supported via modular, load balancing job system. Fast graph and matroid based algorithms allow identification equivalent integrals.

Charged gauge boson pair production at the Large Hadron Collider allows detailed probes of fundamental structure electroweak interactions. We present precise theoretical predictions for on-shell W+ W- that include, first time, QCD effects up to next leading order in perturbation theory. As compared order, inclusive cross section is enhanced by 9% 7 TeV and 12% 14 TeV. The residual perturbative uncertainty 3% level. severe contamination due top-quark resonances discussed detail. Comparing...

Integration by parts reduction is a standard component of most modern multi-loop calculations in quantum field theory. We present novel strategy constructed to overcome the limitations currently available programs based on Laporta's algorithm. The key idea construct algebraic identities from numerical samples obtained reductions over finite fields. expect method be highly amenable parallelization, show low memory footprint during step, and allow for significantly better run-times.

We calculate the complete quark and gluon cusp anomalous dimensions in four-loop massless QCD analytically from first principles. In addition, we determine matter dependence of collinear dimensions. Our approach is to Laurent expand form factors parameter dimensional regularization. employ finite field syzygy techniques reduce relevant Feynman integrals a basis integrals, subsequently evaluate directly their standard parametric representations.

We compute all helicity amplitudes for the scattering of five partons in two-loop QCD relevant flavor configurations, retaining contributing color structures. employ tensor projection to obtain ’t Hooft-Veltman scheme starting from a set primitive amplitudes. Our analytic results are expressed terms massless pentagon functions, and easy evaluate numerically. These provide important input investigations soft-collinear factorization studies high-energy limit. Published by American Physical Society 2024

We compute the full set of two-loop Feynman integrals appearing in massless four-point functions with two off-shell legs same invariant mass. These allow to determine corrections amplitudes for vector boson pair production at hadron colliders, $ q\overline{q} → VV , and thus this process next-to- next-to-leading order accuracy QCD. The master are derived using method differential equations, employing a canonical basis integrals. obtain analytical results all integrals, expressed terms...

The pure singlet asymptotic heavy flavor corrections to 3-loop order for the deep-inelastic scattering structure function $F_2(x,Q^2)$ and corresponding transition matrix element $A_{Qq}^{(3), \sf PS}$ in variable number scheme are computed. In Mellin-$N$ space these inclusive quantities depend on generalized harmonic sums. We also recalculate complete anomalous dimension first time. Numerical results Wilson coefficients, operator contribution presented.

We calculate the massive flavor non-singlet Wilson coefficient for heavy contributions to structure function $F_2(x,Q^2)$ in asymptotic region $Q^2 \gg m^2$ and associated operator matrix element $A_{qq,Q}^{(3), \rm NS}(N)$ 3-loop order Quantum Chromodynamics at general values of Mellin variable $N$. This is vector current axial even odd moments $N$, respectively. also corresponding elements transversity, compute anomalous dimensions $O(N_F)$ compare results literature. The matching...

In this paper, we study phenomenologically interesting soft radiation distributions in massless QCD. Specifically, consider the emission of two partons off a pair light-like Wilson lines, either fundamental or adjoint representation, at next-to-leading order. Our results are an essential component next-to-next-to-next-to-leading order threshold corrections to both Higgs boson production gluon fusion channel and Drell-Yan lepton production. calculations consistent with recently published for...

The authors compute certain (soft-virtual) corrections to the Higgs boson production in gluon-gluon fusion at next-to-next-to-next-to-leading order QCD. Such higher loop calculations are essential for comparing theoretical predictions with experimental results of LHC.

We consider Feynman integrals with algebraic leading singularities and total differentials in $\ensuremath{\epsilon}\text{ }\mathrm{d}\text{ }\mathrm{ln}$ form. show for the first time that it is possible to evaluate involving unrationalizable roots terms of conventional multiple polylogarithms, by either parametric integration or matching symbol. As our main application, we two-loop master relevant $\ensuremath{\alpha}{\ensuremath{\alpha}}_{s}$ corrections Drell-Yan lepton pair production...

A bstract The scale evolution of parton distributions is determined by universal splitting functions. As a milestone towards the computation these functions to four-loop order in QCD, we compute all contributions pure-singlet quark-quark that involve two closed fermion loops. are extracted from pole terms off-shell operator matrix elements, and workflow for their calculation outlined. We reproduce known results non-singlet validate our new against fixed Mellin moments.

The unpolarized and polarized massive operator matrix elements AQg(3) ΔAQg(3) contain first–order factorizable non–first–order contributions in the determining difference or differential equations of their master integrals. We compute single heavy mass case for all contributing Feynman diagrams. Moreover, we present complete color–ζ factors cases which also emerge integrals, but cancel final result as found by using method arbitrary high Mellin moments. Individual depend on generalized...

We compute the two-loop massless QCD corrections to helicity amplitudes for production of two electroweak gauge bosons in gluon fusion channel, gg → V 1 2, keeping virtuality vector and 2 arbitrary taking their decays into leptons account. The are expressed terms master integrals, whose representation has been optimised fast reliable numerical evaluation. provide analytical results a public C++ code evaluation on HepForge at http://vvamp.hepforge.org .

We calculate the massive operator matrix element $A_{gq}^{(3)}(N)$ to 3-loop order in Quantum Chromodynamics at general values of Mellin variable $N$. This is first complete transition function needed flavor number scheme obtained $O(α_s^3)$. A independent recalculation performed for contributions $\propto N_F$ anomalous dimension $γ_{gq}^{(2)}(N)$.

We consider the analytic calculation of a two-loop non-planar three-point function which contributes to amplitudes for $t \bar{t}$ production and $\gamma \gamma$ in gluon fusion through massive top-quark loop. All subtopology integrals can be written terms multiple polylogarithms over an irrational alphabet we employ new method integration differential equations does not rely on rationalization latter. The top topology integrals, instead, spite absence three-particle cut, cannot evaluated...

We compute the two-loop massless QCD corrections to helicity amplitudes for production of two massive vector bosons in quark-antiquark annihilation, allowing an arbitrary virtuality bosons: $q \bar q' \to V_1V_2$. Combining with leptonic decay currents, we obtain full description corresponding electroweak four-lepton processes. The calculation is performed by projecting diagrams onto appropriate basis Lorentz structures. All Feynman integrals are reduced a master integrals, which then...

We present a new method for the decomposition of multi-loop Euclidean Feynman integrals into quasi-finite integrals. These are defined in shifted dimensions with higher powers propagators, make explicit both infrared and ultraviolet divergences, allow an immediate trivial expansion parameter dimensional regularization. Our approach avoids introduction spurious structures thereby leaves particularly accessible to direct analytical integration techniques. Alternatively, resulting convergent...

We calculate the four-loop massless QCD corrections with three closed quark lines to and gluon form factors. apply a novel integration by parts algorithm based on modular arithmetic compute all relevant master integrals for arbitrary values of space-time dimension. This is first calculation factor at this perturbative order in QCD.

A bstract We present the leading colour and light fermionic planar two-loop corrections for production of two photons a jet in quark-antiquark quark-gluon channels. In particular, we compute interference amplitudes with corresponding tree level ones, summed over colours polarisations. Our calculation uses latest advancements algorithms integration-by-parts reduction multivariate partial fraction decomposition to produce compact easy-to-use results. have implemented our results an efficient...

We calculate the collinear anomalous dimensions in massless four-loop QCD and $\mathcal{N} = 4$ supersymmetric Yang-Mills theory from infrared poles of vertex form factors. give very precise numerical approximations a conjecture for complete analytic results both models we consider.