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Related papers: Three loop master integrals for ${\mathcal{O}} (\a…

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We present the color planar and complete light quark QCD contributions to the three loop heavy quark form factors in the case of vector, axial-vector, scalar and pseudo-scalar currents. We evaluate the master integrals applying a new method…

High Energy Physics - Phenomenology · Physics 2018-07-18 Jakob Ablinger , Johannes Bluemlein , Peter Marquard , Narayan Rana , Carsten Schneider

The three-loop form factors in massless QCD can be expressed as a linear combination of master integrals. Besides a number of master integrals which factorise into products of one-loop and two-loop integrals, one finds 16 genuine three-loop…

High Energy Physics - Phenomenology · Physics 2010-04-05 T. Gehrmann , G. Heinrich , T. Huber , C. Studerus

We compute the master integrals containing 2 and 3 massive propagators entering the planar amplitudes of the 2-loop electroweak form factor. The masses of the $W$, $Z$ and Higgs bosons are assumed to be degenerate. This work is a…

High Energy Physics - Phenomenology · Physics 2009-11-10 U. Aglietti , R. Bonciani

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 compute two-loop electroweak corrections to double Higgs boson production in gluon fusion mediated by light quarks in a fully analytical way. We determine a basis of master integrals satisfying canonical differential equations in…

High Energy Physics - Phenomenology · Physics 2025-06-03 Marco Bonetti , Philipp Rendler , William J. Torres Bobadilla

In this letter we continue the calculation of master integrals for massless three-loop form factors by giving analytical results for those integrals which are relevant for the fermionic contributions proportional to N_F^2, N_F*N, and N_F/N.…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Heinrich , T. Huber , D. Maitre

Recent results on the calculation of 3-loop massive operator matrix elements in case of one and two heavy quark masses are reported. They concern the $O(n_f T_F^2 C_{F,A})$ and $O(T_F^2 C_{F,A})$ gluonic corrections, two-mass quarkonic…

High Energy Physics - Phenomenology · Physics 2016-08-14 J. Ablinger , J. Blümlein , A. De Freitas , A. Hasselhuhn , S. Klein , C. Raab , M. Round , C. Schneider , F. Wißbrock

We compute the contribution of three-loop mixed QCD-electroweak corrections ($\alpha_S^2\alpha^2$) to the $gg \to H$ scattering amplitude. We employ the method of differential equations to compute the relevant integrals and express them in…

High Energy Physics - Phenomenology · Physics 2018-05-10 Marco Bonetti , Kirill Melnikov , Lorenzo Tancredi

We compute three-loop corrections to the singlet form factors for massive quarks using a semi-analytic method which provides precise results over the whole kinematic range. Particular emphasis is put on the anomaly contribution originating…

High Energy Physics - Phenomenology · Physics 2023-05-24 Matteo Fael , Fabian Lange , Kay Schönwald , Matthias Steinhauser

We studied the two-loop non-factorizable Feynman diagrams for the $t$-channel single-top production process in quantum chromodynamics. We present a systematic computation of master integrals of the two-loop Feynman diagrams with one…

High Energy Physics - Phenomenology · Physics 2023-07-12 Zihao Wu , Ming-Ming Long

We study a set of two-loop non-planar master integrals needed for the NNLO QCD corrections to diphoton and dijet production at hadron colliders. The top-sector topology contains an internal massive fermion loop and is known to contain…

High Energy Physics - Theory · Physics 2024-02-13 Taushif Ahmed , Ekta Chaubey , Mandeep Kaur , Sara Maggio

We compute the complete set of two-loop master integrals for the scattering of four massless particles and a massive one. Our results are ready for phenomenological applications, removing a major obstacle to the computation of complete…

High Energy Physics - Phenomenology · Physics 2024-05-03 Samuel Abreu , Dmitry Chicherin , Harald Ita , Ben Page , Vasily Sotnikov , Wladimir Tschernow , Simone Zoia

We calculate convergent 3-loop Feynman diagrams containing a single massive loop equipped with twist $\tau =2$ local operator insertions corresponding to spin $N$. They contribute to the massive operator matrix elements in QCD describing…

High Energy Physics - Phenomenology · Physics 2015-06-19 Jakob Ablinger , Johannes Blümlein , Clemens Raab , Carsten Schneider , Fabian Wißbrock

Multi-loop integrals can be evaluated numerically using Mellin-Barnes representations. Here this technique is applied to the calculation of electroweak two-loop correction with closed fermion loops for two observables: the effective weak…

High Energy Physics - Phenomenology · Physics 2013-10-14 A. Freitas , Yi-Cheng Huang

The quarkonic contributions to the three-loop heavy-quark form factors for vector, axial-vector, scalar and pseudoscalar currents are described by closed form difference equations for the expansion coefficients in the limit of small…

High Energy Physics - Phenomenology · Physics 2023-07-07 Johannes Blümlein , Abilio De Freitas , Peter Marquard , Narayan Rana , Carsten Schneider

We compute the master integrals containing one massive propagator entering the two-loop electroweak form factor, i.e. the process f fbar --> X, where f fbar is an on-shell massless fermion pair and X is a singlet particle under SU(2)L x…

High Energy Physics - Phenomenology · Physics 2009-11-10 U. Aglietti , R. Bonciani

We analytically compute the four-loop QCD corrections for the colour structure $(d_F^{abcd})^2$ to the massless non-singlet quark form factor. The computation involves non-trivial non-planar integral families which have master integrals in…

High Energy Physics - Phenomenology · Physics 2019-03-27 Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We compute the complete two-loop electroweak corrections to the Higgsstralung process $e^+e^-\rightarrow HZ$ at the future Higgs factory. The Feynman integrals involved in the computation are decomposed into linear combinations of a minimal…

High Energy Physics - Phenomenology · Physics 2023-07-12 Xiang Chen , Xin Guan , Chuan-Qi He , Zhao Li , Xiao Liu , Yan-Qing Ma

We describe a new method of calculation of generic multi-loop master integrals based on the numerical solution of systems of difference equations in one variable. We show algorithms for the construction of the systems using…

High Energy Physics - Phenomenology · Physics 2009-07-09 S. Laporta

The $tW$ associated production has the second-largest cross section among three single top production channels. A complete study of NNLO QCD corrections to $tW$ production is still missing in literature. We present the calculation of part…

High Energy Physics - Phenomenology · Physics 2021-11-30 Ming-Ming Long , Ren-You Zhang , Wen-Gan Ma , Yi Jiang , Liang Han , Zhe Li , Shuai-Shuai Wang