English
Related papers

Related papers: Recursive Approach to One-loop QCD Matrix Elements

200 papers

Starting with the recursive extended Euclid's algorithm, we apply a systematic approach using matrix notation to transform it into an iterative algorithm. The partial correctness proof derived from the transformation turns out to be very…

Discrete Mathematics · Computer Science 2016-07-04 Hing Leung

We apply the Quasi Monte Carlo (QMC) and recursive numerical integration methods to evaluate the Euclidean, discretized time path-integral for the quantum mechanical anharmonic oscillator and a topological quantum mechanical rotor model.…

High Energy Physics - Lattice · Physics 2016-01-26 A. Ammon , A. Genz , T. Hartung , K. Jansen , H. Leövey , J. Volmer

I present one-loop perturbative calculations of matching coefficients between matrix elements in continuum regulated QCD and lattice QCD with overlap fermions, with emphasis a recently-proposed variant discretization of the overlap. These…

High Energy Physics - Lattice · Physics 2016-09-01 Thomas DeGrand

In this contribution we provide further details to the recent calculation of QCD corrections to massive three-loop form factors presented in Ref. [1].

High Energy Physics - Phenomenology · Physics 2018-07-26 Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

The usefulness of recursive equations to compute scattering matrix elements for arbitrary processes is discussed. Explicit results at tree and one-loop order, obtained by the HELAC/PHEGAS package that is based on the Dyson-Schwinger…

High Energy Physics - Phenomenology · Physics 2009-11-11 P. Draggiotis , A. van Hameren , R. Kleiss , A. Lazopoulos , C. G. Papadopoulos , M. Worek

We compute the one-loop corrections to \tth up to order $\mathcal{O}(\epsilon^2)$ in the dimensional regularization parameter. We apply the projector method to compute polarized amplitudes, which generalize massless helicity amplitudes to…

High Energy Physics - Phenomenology · Physics 2023-12-18 Federico Buccioni , Philipp Alexander Kreer , Xiao Liu , Lorenzo Tancredi

A numerical approach to compute tensor integrals in one-loop calculations is presented. The algorithm is based on a recursion relation which allows to express high rank tensor integrals as a function of lower rank ones. At each level of…

High Energy Physics - Phenomenology · Physics 2010-02-03 F. del Aguila , R. Pittau

A simple recursive scheme for parameterisation of n-by-n unitary matrices is presented.

Mathematical Physics · Physics 2009-11-11 C. Jarlskog

We compute the ${\cal O}(\alpha_s^3)$ virtual QCD corrections to the $\gamma^*\to q\bar q g$ matrix element arising from the interference of the two-loop with the tree-level amplitude and from the self-interference of the one-loop…

High Energy Physics - Phenomenology · Physics 2010-04-06 L. W. Garland , T. Gehrmann , E. W. N. Glover , A. Koukoutsakis , E. Remiddi

In this paper we address the problem of translating one-way quantum computation (1WQC) into the circuit model. We start by giving a straightforward circuit representation of any 1WQC, at the cost of introducing many ancilla wires. We then…

Quantum Physics · Physics 2013-07-22 Raphael Dias da Silva , Ernesto F. Galvão

We review the subject of QCD inequalities, using both a Hamiltonian variational approach, and a rigorous Euclidean path integral approach.

High Energy Physics - Phenomenology · Physics 2011-07-19 Shmuel Nussinov , Melissa A. Lampert

We present a perturbative approach to QCD based on quark composites, that is barions and mesons, as fundamental variables.

High Energy Physics - Phenomenology · Physics 2007-05-23 Sergio Caracciolo , Gianni De Franceschi , Fabrizio Palumbo

The lectures are a practical introduction to perturbative calculations in QED and QCD. I discuss methods of calculation of one- and two-loop diagrams in dimensional regularization, MSbar and on-shell renormalization schemes, decoupling of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrey Grozin

We discuss a practical approach to compute master integrals entering physical quantities which depend on one parameter. As an example we consider four-loop QCD corrections to the relation between a heavy quark mass defined in the…

High Energy Physics - Phenomenology · Physics 2021-10-11 Matteo Fael , Fabian Lange , Kay Schönwald , Matthias Steinhauser

In order to meet the precision requirements for the LHC and future colliders, next-to-next-to-leading order corrections to a wide range of processes are essential, making general automated tools highly desirable. Extending the strategy of…

High Energy Physics - Phenomenology · Physics 2026-03-09 Fabian Lange , Max F. Zoller

We recently presented a new method for the evaluation of one-loop amplitude of arbitrary scattering processes, in which the reduction to scalar integrals is performed at the integrand level. In this talk, we review the main features of the…

High Energy Physics - Phenomenology · Physics 2007-09-17 Giovanni Ossola

In this talk we discuss the color decomposition of tree-level and one-loop QCD amplitudes with arbitrary numbers of quarks and gluons. We present a method for the decomposition of partial amplitudes into primitive amplitudes, which is based…

High Energy Physics - Phenomenology · Physics 2014-07-03 Christian Reuschle , Stefan Weinzierl

The systematic approach to solving the recurrence relations for multi-loop integrals is described. In particular, the criteria of their reducibility is suggested.

High Energy Physics - Phenomenology · Physics 2007-05-23 P. A. Baikov

We give an analytic formula for the double distribution of hadronic invariant mass and charged lepton energy to one-loop order of the perturbative QCD. Although infrared singular, this quantity is closely related to physical observables…

High Energy Physics - Phenomenology · Physics 2011-04-15 M. Jezabek , P. Urban

In this note, we study the $\mathcal{Q}$-cut representation by combining it with BCFW deformation. As a consequence, the one-loop integrand is expressed in terms of a recursion relation, i.e., $n$-point one-loop integrand is constructed…

High Energy Physics - Theory · Physics 2017-02-01 Bo Feng , Song He , Rijun Huang , Ming-xing Luo