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Related papers: Tree-level soft emission for two pairs of quarks

200 papers

We study higher-order QCD corrections for the associated production of a top-antitop quark pair and a photon ($t{\bar t}\gamma$ production) in proton-proton collisions. We calculate the approximate NNLO cross section, with second-order…

High Energy Physics - Phenomenology · Physics 2023-03-01 Nikolaos Kidonakis , Alberto Tonero

The calculations for the production of heavy quarks in deeply inelastic scattering (DIS) can be seen as an illustrative example in the framework of perturbative Quantum Chromo Dynamics (pQCD). In this thesis, I give an overview of all steps…

High Energy Physics - Phenomenology · Physics 2020-05-18 Felix Hekhorn

Recently, we evaluated the virtual cross-section for Bhabha scattering in pure QED, up to corrections of order alpha^4 (N_F =1). This calculation is valid for arbitrary values of the squared center of mass energy s and momentum transfer t;…

High Energy Physics - Phenomenology · Physics 2009-11-10 R. Bonciani , A. Ferroglia , P. Mastrolia , E. Remiddi , J. J. van der Bij

Tree-level double-color-ordered amplitudes are computed using Berends--Giele recursion relations applied to the bi-adjoint cubic scalar theory. The standard notion of Berends--Giele currents is generalized to double-currents and their…

High Energy Physics - Theory · Physics 2016-08-24 Carlos R. Mafra

We compute the one-loop (hard) matching correction to heavy-to-light transition currents in soft-collinear effective theory (SCET) to sub-leading power in the SCET expansion parameter for an arbitrary Dirac structure of the QCD weak…

High Energy Physics - Phenomenology · Physics 2010-04-05 M. Beneke , Y. Kiyo , D. s. Yang

I describe how to calculate cross sections for hard-scattering processes in high energy collisions at next to leading order in QCD. I consider infrared-safe quantities and I assume that the scattering amplitudes are known in analytic form…

High Energy Physics - Phenomenology · Physics 2007-05-23 Z. Kunszt

We describe predictions for top-quark pair differential distributions at hadron colliders, which combine state-of-the-art NNLO QCD calculations and NLO electroweak corrections together with double resummation at NNLL$'$ accuracy of…

Methods from Quantum Information Theory are used to scrutinize quantum correlations encoded in the two-quark density matrix over light-cone momentum fractions $x_1$ and $x_2$. A non-perturbative three quark model light-cone wavefunction…

High Energy Physics - Phenomenology · Physics 2025-10-01 Adrian Dumitru , Eric Kolbusz

We present the derivation of the NNLO two-parton final state contributions to top pair production in the quark-antiquark channel proportionnal to the leading colour factor $N_c^2$. Together with the three and four-parton NNLO contributions…

High Energy Physics - Phenomenology · Physics 2016-01-27 Gabriel Abelof , Aude Gehrmann-De Ridder , Imre Majer

We determine the analytic expression of the damping rates for very soft moving quarks in an expansion to second order in powers of their momentum in the context of QCD at high temperature. The calculation is performed using the…

High Energy Physics - Phenomenology · Physics 2009-01-07 A. Abada , K. Bouakaz , N. Daira-Aifa

We present a comprehensive study of the production of top quark pairs in association with one hard jet in the di-lepton decay channel at the LHC. Our predictions, accurate at NLO in QCD, focus on the LHC Run II with a center-of-mass energy…

High Energy Physics - Phenomenology · Physics 2016-11-28 G. Bevilacqua , H. B. Hartanto , M. Kraus , M. Worek

The differential cross-sections for elastic and inelastic neutrino-deuteron scattering are calculated analytically using nucleon-nucleon effective field theory. For elastic scattering, the deuteron axial form factor and the deuteron strange…

Nuclear Theory · Physics 2009-10-31 Malcolm Butler , Jiunn-Wei Chen

We compute the soft real photon emission rate from the QCD matter in the vicinity of the critical line at moderate density and the temperature approaching the critical one from above. The obtained production rate exhibits a steep rise close…

High Energy Physics - Phenomenology · Physics 2020-12-30 B. O. Kerbikov

We study the behavior of the tree-level S-matrix of a variety of theories as two particles become soft. By analogy with the recently found subleading soft theorems for gravitons and gluons, we explore subleading terms in double soft…

High Energy Physics - Theory · Physics 2015-10-07 Freddy Cachazo , Song He , Ellis Ye Yuan

We give a selection of results on spectrum and decay constants of light and heavy-light hadrons. Effective field theories relevant for their lattice calculation, namely non-relativistic QCD (NRQCD) for heavy quarks on the lattice and Chiral…

High Energy Physics - Lattice · Physics 2009-09-29 A. Ali Khan

For top quark decays into heavy quark mesons $\Upsilon$ and $\bar{B}_c^*$ , a complete calculation to the leading order both in QCD coupling constant $\alpha_s$ and in $v$, the typical velocity of the heavy quarks inside the mesons, is…

High Energy Physics - Phenomenology · Physics 2011-07-19 Cong-Feng Qiao , Chong Sheng Li , Kuang-Ta Chao

There exists a large field for phenomenological models in which the knowledge of the structure of hadrons in terms of QCD constituents obtained from deep inelastic scatterings is related to their behaviour in soft processes. One of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Nyiri

We apply heavy-quark effective theory to separate long- and short-distance effects of heavy quarks in lattice gauge theory. In this approach, the inverse heavy-quark mass and the lattice spacing are treated as short distances, and their…

High Energy Physics - Lattice · Physics 2014-11-17 Junpei Harada , Shoji Hashimoto , Ken-Ichi Ishikawa , Andreas S. Kronfeld , Tetsuya Onogi , Norikazu Yamada

We review QCD based descriptions of diffractive deep inelastic scattering emphasising the role of models with parton saturation. These models provide natural explanation of such experimentally observed facts as the constant ratio of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Golec-Biernat

The combination of collinear factorization with effective field theory originally developed for soft interactions of heavy quarks provides the foundations of the theory of exclusive and semi-inclusive B decays. In this article I summarize…

High Energy Physics - Phenomenology · Physics 2015-01-30 M. Beneke