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Related papers: Massive QCD amplitudes at higher orders

200 papers

The associated production of a photon and a top-antitop quark pair ($t\bar{t}\gamma$) is important for measuring the top-quark charge and probing the top-photon interaction, and it requires improved theoretical predictions. We focus on the…

High Energy Physics - Phenomenology · Physics 2025-10-03 Guoxing Wang , Li Lin Yang

In the limit where partons become collinear to each other, scattering amplitudes factorize into a product of universal, process-independent building blocks and scattering amplitudes involving fewer partons. We compute these universal…

High Energy Physics - Phenomenology · Physics 2024-08-07 Xin Guan , Franz Herzog , Yao Ma , Bernhard Mistlberger , Adi Suresh

We extend the discussion of the recently discovered 'anomaly poles' in QCD Compton scattering. We perform the complete one-loop calculation of the Compton amplitude using momentum transfer $t$ as the regulator of collinear divergences. In…

High Energy Physics - Phenomenology · Physics 2023-07-25 Shohini Bhattacharya , Yoshitaka Hatta , Werner Vogelsang

We show that the controversies on the gauge dependence and the infrared singularity emerged in the generalized factorization approach for nonleptonic heavy meson decays within the framework of the operator product expansion can be resolved…

High Energy Physics - Phenomenology · Physics 2009-10-31 Hai-Yang Cheng , Hsiang-nan Li , Kwei-Chou Yang

We report on the recent completion of the three-loop calculation of the soft anomalous dimension in massless gauge-theory scattering amplitudes. This brings the state-of-the-art knowledge of long-distance singularities in multi-leg QCD…

High Energy Physics - Phenomenology · Physics 2016-06-21 Einan Gardi , Øyvind Almelid , Claude Duhr

We review the state-of-the-art knowledge of IR singularities in multileg QCD amplitudes, identifying the key reasons for the remarkable simplicity of the soft anomalous dimension. We then present a novel strategy to compute this quantity…

High Energy Physics - Phenomenology · Physics 2026-04-22 Einan Gardi , Zehao Zhu

We update the leading order in $\alpha_s$ QCD amplitude for deep exclusive neutrino and antineutrino production of a light meson on an unpolarized nucleon. The factorization theorems of the collinear QCD approach allow us to write the…

High Energy Physics - Phenomenology · Physics 2017-07-05 B. Pire , L. Szymanowski , J. Wagner

Gravitational Compton scattering process with a massive fermion is studied in the context of the linearized gravity. Gravitational gauge invariance and graviton transversality cause the transition amplitude to be factorized into that of…

High Energy Physics - Phenomenology · Physics 2010-11-01 S. Y. Choi , J. S. Shim , H. S. Song

In the large momentum transfer limit, generalized parton distributions can be calculated through a QCD factorization theorem which involves perturbatively-calculable hard kernels and light-cone parton distribution amplitudes of hadrons. We…

High Energy Physics - Phenomenology · Physics 2009-11-10 Pervez Hoodbhoy , Xiangdong Ji , Feng Yuan

We compute two-loop helicity amplitudes in QCD for diphoton production through quark- and gluon-initiated channels, accounting for a massive internal quark loop by keeping its full mass dependence. Using physical projectors, we directly…

High Energy Physics - Phenomenology · Physics 2025-02-06 Taushif Ahmed , Amlan Chakraborty , Ekta Chaubey , Mandeep Kaur

Scattering amplitudes of partons in QCD contain infrared divergences which can be resummed to all orders in terms of an anomalous dimension. Independently, in the limit of high-energy forward scattering, large logarithms of the energy can…

High Energy Physics - Phenomenology · Physics 2020-05-20 Simon Caron-Huot , Einan Gardi , Joscha Reichel , Leonardo Vernazza

The study of QCD scattering amplitudes in the collinear regime provides crucial insight into the factorization properties of hadronic cross sections. In this paper, we present the first complete results for two-loop spacelike splitting…

High Energy Physics - Phenomenology · Physics 2026-04-01 Federico Buccioni , Hanyu Fang , Kai Yan

I review the recent progress in the evaluation of two-loop massive QCD amplitudes necessary for the description of hadronic scattering processes at the LHC. I put a special emphasis on the case of top-quark final states.

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Czakon

Two-loop QCD correction to massive spin-2 Graviton decaying to $q ~ + ~ \bar{q}~ + ~g$ is presented considering a generic universal spin-2 coupling to the SM through the conserved energy-momentum tensor. Such a massive spin-2 particle can…

High Energy Physics - Phenomenology · Physics 2016-12-21 Taushif Ahmed , Goutam Das , Prakash Mathews , Narayan Rana , V. Ravindran

We review recent advances in the theory of strong-interaction effects and final-state interactions in hadronic weak decays of heavy mesons. In the heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can be calculated…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthias Neubert

In this paper, we present analytical results for the two-loop QCD corrections to the production of two partons or a photon and a parton in hadronic collisions, mediated by loops of massive quarks. These amplitudes involve Feynman integrals…

High Energy Physics - Phenomenology · Physics 2025-09-22 Federico Coro , Christoph Nega , Lorenzo Tancredi , Fabian J. Wagner

The consistent construction of scattering amplitudes for processes with off-shell initial partons and involving electro-weak interactions is addressed.

High Energy Physics - Phenomenology · Physics 2019-02-06 A. van Hameren

We investigate the production of highly energetic top-quark pairs at hadron colliders, focusing on the case where the invariant mass of the pair is much larger than the mass of the top quark. In particular, we set up a factorization…

High Energy Physics - Phenomenology · Physics 2013-05-30 Andrea Ferroglia , Ben D. Pecjak , Li Lin Yang

We demonstrate a factorization formula for semi-inclusive deep-inelastic scattering with hadrons in the current fragmentation region detected at low transverse momentum. To facilitate the factorization, we introduce the transverse-momentum…

High Energy Physics - Phenomenology · Physics 2011-08-01 Xiangdong Ji , Jian-ping Ma , Feng Yuan

We present two novel results about the universal structure of radiative QED amplitudes in the soft and in the collinear limit. On the one hand, we extend the well-known Low-Burnett-Kroll theorem to the one-loop level and give the explicit…

High Energy Physics - Phenomenology · Physics 2022-05-04 Tim Engel , Adrian Signer , Yannick Ulrich