English
Related papers

Related papers: Caravel: A C++ Framework for the Computation of Mu…

200 papers

We show how to extract the coefficients of the 4-, 3-, 2- and 1-point one-loop scalar integrals from the full one-loop amplitude of arbitrary scattering processes. In a similar fashion, also the rational terms can be derived. Basically no…

High Energy Physics - Phenomenology · Physics 2008-11-26 Giovanni Ossola , Costas G. Papadopoulos , Roberto Pittau

We present methods for the numerical evaluation of the master integrals that appear in the calculation of scattering amplitudes at higher order in perturbative quantum field theory. We follow the general strategy of solving first-order…

High Energy Physics - Phenomenology · Physics 2025-01-06 Renato Maria Prisco , Jonathan Ronca , Francesco Tramontano

We compute the two-loop helicity amplitudes for the scattering of five gluons, including all contributions beyond the leading-color approximation. The analytic expressions are represented as linear combinations of transcendental functions…

High Energy Physics - Phenomenology · Physics 2024-05-15 Giuseppe De Laurentis , Harald Ita , Maximillian Klinkert , Vasily Sotnikov

We present a new procedure using on-shell recursion to determine coefficients of integral functions appearing in one-loop scattering amplitudes of gauge theories, including QCD. With this procedure, coefficients of integrals, including…

High Energy Physics - Phenomenology · Physics 2009-11-11 Zvi Bern , N. E. J. Bjerrum-Bohr , David C. Dunbar , Harald Ita

We report on the development of tools to calculate loop integrals and amplitudes beyond one loop. In particular, we review new features of the program SecDec which can be used for the numerical evaluation of parametric integrals like…

High Energy Physics - Phenomenology · Physics 2016-12-21 S. Borowka , G. Heinrich , S. Jahn , S. P. Jones , M. Kerner , J. Schlenk , T. Zirke

Calculation of amplitudes in perturbative quantum field theory involve large loop integrals. The complexity of those integrals, in combination with the large number of Feynman diagrams, make the calculations very difficult. Reduction…

High Energy Physics - Phenomenology · Physics 2015-06-05 Ronald H. P. Kleiss , Ioannis Malamos , Costas G. Papadopoulos , Rob Verheyen

We present a C++ library for the numerical evaluation of one-loop virtual corrections to multi-jet production in massless QCD. The pure gluon primitive amplitudes are evaluated using NGluon. A generalized unitarity reduction algorithm is…

High Energy Physics - Phenomenology · Physics 2015-06-11 Simon Badger , Benedikt Biedermann , Peter Uwer , Valery Yundin

We present recent developments on the topic of the integrand reduction of scattering amplitudes. Integrand-level methods allow to express an amplitude as a linear combination of Master Integrals, by performing operations on the…

High Energy Physics - Phenomenology · Physics 2013-12-06 Hans van Deurzen , Gionata Luisoni , Pierpaolo Mastrolia , Edoardo Mirabella , Giovanni Ossola , Tiziano Peraro , Ulrich Schubert

We have calculated the one-loop scattering amplitude of an electron by an external Coulomb potential in QED free of infrared divergences. This feature is achieved by applying the Faddeev-Kulish formalism, which implies a redefinition of…

High Energy Physics - Phenomenology · Physics 2024-11-15 J. A. Oller , Marcela Peláez

We find that scattering amplitudes in massive scalar QCD can manifest the duality between color and kinematics at loop-level. Specifically we construct the one-loop integrands for four-point scattering between two distinct massive scalars,…

High Energy Physics - Theory · Physics 2021-02-10 John Joseph M. Carrasco , Ingrid A. Vazquez-Holm

We review the current status of high-multiplicity double-virtual QCD corrections to processes relevant for LHC phenomenology. In particular, we discuss the recent full-color calculation of the five-parton process, whose two-loop amplitudes…

High Energy Physics - Phenomenology · Physics 2024-06-27 Giuseppe De Laurentis

We review the recent progress on the numerical implementation of the Loop-Tree Duality Method (LTDM) for the calculation of scattering amplitudes. A central point is the analysis of the singularities of the integrand. In the framework of…

High Energy Physics - Phenomenology · Physics 2015-09-25 Sebastian Buchta , Grigorios Chachamis , Petros Draggiotis , Ioannis Malamos , German Rodrigo

We provide a new efficient diagrammatic tool, in the context of the scattering equations, for computation of covariant $D$-dimensional tree-level $n$-point amplitudes with pairs of spinning massive particles using compact exponential…

High Energy Physics - Theory · Physics 2021-05-12 N. Emil J. Bjerrum-Bohr , Taro V. Brown , Humberto Gomez

We show, for previously uncalculated examples containing a uniform mass in the loop, that it is possible to obtain complete massive one-loop gauge theory amplitudes solely from unitarity and known ultraviolet or infrared mass singularities.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Z. Bern , A. G. Morgan

A number theoretic algorithm is given for writing gauge theory amplitudes in a compact manner. It is possible to write down all details of the complete $L$ loop amplitude with two integers, or a complex integer. However, a more symmetric…

General Physics · Physics 2007-05-23 Gordon Chalmers

SAMURAI is a tool for the automated numerical evaluation of one-loop corrections to any scattering amplitudes within the dimensional-regularization scheme. It is based on the decomposition of the integrand according to the OPP-approach,…

High Energy Physics - Phenomenology · Physics 2014-11-21 P. Mastrolia , G. Ossola , T. Reiter , F. Tramontano

Quantum algorithms are a very promising field. However, creating and manipulating these kind of algorithms is a very complex task, specially for software engineers used to work at higher abstraction levels. The work presented here is part…

We present the first open release of the DCA++ project, a high-performance research software framework to solve quantum many-body problems with cutting edge quantum cluster algorithms. DCA++ implements the dynamical cluster approximation…

Scattering amplitudes computed at a fixed loop order, along with any other object computed in perturbative quantum field theory, can be expressed as a linear combination of a finite basis of loop integrals. To compute loop amplitudes in…

High Energy Physics - Phenomenology · Physics 2018-10-04 Alessandro Georgoudis , Kasper J. Larsen , Yang Zhang

An overview is presented on the current status of main mathematical computation methods for the multi-loop corrections to single scale observables in quantum field theory and the associated mathematical number and function spaces and…

High Energy Physics - Phenomenology · Physics 2018-09-19 Johannes Blümlein , Carsten Schneider