English
Related papers

Related papers: Two-loop master integrals for non-leptonic heavy-t…

200 papers

We calculate the complete two-loop QCD amplitudes for hadronic $tW$ production by combining analytical and numerical techniques. The amplitudes have been first reduced to master integrals of eight planar and seven non-planar families, which…

High Energy Physics - Phenomenology · Physics 2023-08-02 Long-Bin Chen , Liang Dong , Hai Tao Li , Zhao Li , Jian Wang , Yefan Wang

We derive the full system of canonical differential equations for all planar two-loop massless six-particle master integrals, and determine analytically the boundary conditions. This fully specifies the solutions, which may be written as…

High Energy Physics - Phenomenology · Physics 2025-01-20 Johannes Henn , Antonela Matijašić , Julian Miczajka , Tiziano Peraro , Yingxuan Xu , Yang Zhang

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

We consider the two-loop corrections to the $HW^+W^-$ vertex at order $\alpha\alpha_s$. We construct a canonical basis for the two-loop integrals using the Baikov representation and the intersection theory. By solving the $\epsilon$-form…

High Energy Physics - Phenomenology · Physics 2022-01-07 Chichuan Ma , Yuxuan Wang , Xiaofeng Xu , Li Lin Yang , Bin Zhou

We present the calculation of all non-planar master integrals that are needed to describe production of two off-shell vector bosons in collisions of two massless partons through NNLO in perturbative QCD. The integrals are computed…

High Energy Physics - Phenomenology · Physics 2015-06-19 Fabrizio Caola , Johannes M. Henn , Kirill Melnikov , Vladimir A. Smirnov

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 evaluate in the framework of QCD factorization the two-loop vertex corrections to the decays $\bar{B}_{(s)}\to D_{(s)}^{(\ast)+} \, L^-$ and $\Lambda_b \to \Lambda_c^+ \, L^-$, where $L$ is a light meson from the set…

High Energy Physics - Phenomenology · Physics 2016-10-12 Tobias Huber , Susanne Kränkl , Xin-Qiang Li

We present the Master Integrals needed for the calculation of the two-loop QCD corrections to the forward-backward asymmetry of a quark-antiquark pair produced in electron-positron annihilation events. The abelian diagrams entering in the…

High Energy Physics - Phenomenology · Physics 2009-11-10 R. Bonciani , P. Mastrolia , E. Remiddi

QCD in non-integer d=4-2 epsilon space-time dimensions possesses a nontrivial critical point and enjoys exact scale and conformal invariance. This symmetry imposes nontrivial restrictions on the form of the renormalization group equations…

High Energy Physics - Phenomenology · Physics 2015-06-19 V. M. Braun , A. N. Manashov

We present a set of scalar master integrals (MIs) needed for a complete treatment of massive two-loop corrections to Bhabha scattering in QED, including integrals with arbitrary fermionic loops. The status of analytical solutions for the…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. Czakon , J. Gluza , T. Riemann

We describe the analytic calculation of the master integrals required to compute the two-mass three-loop corrections to the $\rho$ parameter. In particular, we present the calculation of the master integrals for which the corresponding…

High Energy Physics - Phenomenology · Physics 2018-07-17 J. Blümlein , A. De Freitas , M. van Hoeij , E. Imamoglu , P. Marquard , C. Schneider

We show how to compute the two-loop sunset integrals at finite volume, for non-degenerate masses and non-zero momentum. We present results for all integrals that appear in the Chiral Perturbation Therory ($\chi$PT) calculation of the…

High Energy Physics - Lattice · Physics 2014-12-03 Johan Bijnens , Emil Boström , Timo A. Lähde

We present the complete set of planar master integrals relevant to the calculation of three-point functions in four-loop massless Quantum Chromodynamics. Employing direct parametric integrations for a basis of finite integrals, we give…

High Energy Physics - Phenomenology · Physics 2019-07-22 Andreas von Manteuffel , Robert M. Schabinger

We numerically compute the two-loop QCD corrections to $Z\gamma$ production at the LHC mediated by light- and heavy-quark box loops. The calculation employs the pipeline of refs. arXiv:2407.18051 and arXiv:2510.18801, which performs Monte…

High Energy Physics - Phenomenology · Physics 2026-03-04 Dario Kermanschah , Matilde Vicini

We present the first numerical results for the two-loop helicity amplitudes for the scattering of four partons and a W-boson in QCD. We use a finite field sampling method to reduce directly from Feynman diagrams to the coefficients of a set…

High Energy Physics - Phenomenology · Physics 2019-07-01 Heribertus Bayu Hartanto , Simon Badger , Christian Brønnum-Hansen , Tiziano Peraro

We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…

High Energy Physics - Phenomenology · Physics 2009-07-29 J. Gluza , A. Mitov , S. Moch , T. Riemann

We discuss recent progress towards extending the Helac framework to the calculation of two-loop amplitudes. A general algorithm for the automated computation of two-loop integrands is described. The algorithm covers all the steps of the…

High Energy Physics - Phenomenology · Physics 2024-01-19 Giuseppe Bevilacqua , Dhimiter Canko , Costas Papadopoulos

We analytically evaluate the master integrals for the second type of planar contributions to the massive two-loop Bhabha scattering in QED using differential equa- tions with canonical bases. We obtain results in terms of multiple…

High Energy Physics - Phenomenology · Physics 2021-10-04 Claude Duhr , Vladimir A. Smirnov , Lorenzo Tancredi

The differential equation in the external invariant p^2 satisfied by the master integral of the general massive 2-loop 4-denominator self-mass diagram is exploited and the expansion of the master integral at p^2=0 is obtained analytically.…

High Energy Physics - Phenomenology · Physics 2010-04-05 M. Caffo , H. Czyz , A. Grzelinska , E. Remiddi

We consider the complete set of planar two-loop five-point Feynman integrals with two off-shell external legs. These integrals are relevant, for instance, for the calculation of the second-order QCD corrections to the production of two…

High Energy Physics - Theory · Physics 2024-11-07 Samuel Abreu , Dmitry Chicherin , Vasily Sotnikov , Simone Zoia