English
Related papers

Related papers: Illustrations of Integrand-Basis Building at Two L…

200 papers

The calculation of the two-loop corrections to the three-jet production rate and to event shapes in electron--positron annihilation requires the computation of a number of two-loop four-point master integrals with one off-shell and three…

High Energy Physics - Phenomenology · Physics 2011-09-29 T. Gehrmann , E. Remiddi

Scattering amplitudes with spinning particles are shown to decompose into multiple copies of simple building blocks to all loop orders, which can be used to efficiently reduce these amplitudes to sums over scalar integrals. Absence of…

High Energy Physics - Phenomenology · Physics 2018-05-28 Rutger H. Boels , Qingjun Jin , Hui Luo

We introduce a novel construction of a contour deformation within the framework of Loop-Tree Duality for the numerical computation of loop integrals featuring threshold singularities in momentum space. The functional form of our contour…

High Energy Physics - Phenomenology · Physics 2020-11-24 Zeno Capatti , Valentin Hirschi , Dario Kermanschah , Andrea Pelloni , Ben Ruijl

In the paper, we give methods of construction of dual bases for the B-spline basis and truncated power basis. Explicit formulas for the dual B-spline basis are obtained using the Legendre-like orthogonal basis of the polynomial spline space…

Numerical Analysis · Mathematics 2017-07-24 Przemysław Gospodarczyk , Paweł Woźny

The two-loop QCD corrections to vector boson pair production at hadron colliders involve a new class of Feynman integrals: two-loop four-point functions with two off-shell external legs. We describe their reduction to a small set of master…

High Energy Physics - Phenomenology · Physics 2013-08-26 Thomas Gehrmann , Lorenzo Tancredi , Erich Weihs

We present a new and fully general algorithm for the automated construction of the integrands of two-loop scattering amplitudes. This is achieved through a generalisation of the open-loops method to two loops. The core of the algorithm…

High Energy Physics - Phenomenology · Physics 2022-07-18 Stefano Pozzorini , Natalie Schär , Max F. Zoller

We report on recent progress for the QCD corrections to top quark pair plus jet production. In particular, we discuss a recent computation for the two-loop master integrals associated to a two-loop five-point pentagon-box integral…

High Energy Physics - Phenomenology · Physics 2023-10-17 Matteo Becchetti

We present the integrand decomposition of multiloop scattering amplitudes in parallel and orthogonal space-time dimensions, $d=d_\parallel+d_\perp$, being $d_\parallel$ the dimension of the parallel space spanned by the legs of the…

High Energy Physics - Phenomenology · Physics 2016-09-21 Pierpaolo Mastrolia , Tiziano Peraro , Amedeo Primo

The full two-loop amplitudes for five massless states in Type~II and Heterotic superstrings are constructed in terms of convergent integrals over the genus-two moduli space of compact Riemann surfaces and integrals of Green functions and…

High Energy Physics - Theory · Physics 2020-07-06 Eric D'Hoker , Carlos R. Mafra , Boris Pioline , Oliver Schlotterer

In this paper, we have made the attempt to classify the integrand basis of all two-loop diagrams in pure four-dimension space-time. Our classification includes the topology of two-loop diagrams which determines the structure of…

High Energy Physics - Phenomenology · Physics 2015-06-11 Bo Feng , Rijun Huang

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

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 present a method for the computation of hepta-cuts of two loop scattering amplitudes. Four dimensional unitarity cuts are used to factorise the integrand onto the product of six tree-level amplitudes evaluated at complex momentum values.…

High Energy Physics - Phenomenology · Physics 2012-04-18 Simon Badger , Hjalte Frellesvig , Yang Zhang

The calculation of the two-loop corrections to the three jet production rate and to event shapes in electron-positron annihilation requires the computation of a number of up to now unknown two-loop four-point master integrals with one…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Gehrmann , E. Remiddi

The integrand-level methods for the reduction of scattering amplitudes are well-established techniques, which have already proven their effectiveness in several applications at one-loop. In addition to the automation and refinement of tools…

High Energy Physics - Phenomenology · Physics 2012-10-05 P. Mastrolia , E. Mirabella , G. Ossola , T. Peraro , H. van Deurzen

We present the values of the complete set of planar four-point Master Integrals needed for massive Bhabha scattering in the limit of fixed angle and high energy at the two-loop level. The integrals have been calculated using direct…

High Energy Physics - Phenomenology · Physics 2010-04-05 M. Czakon , J. Gluza , T. Riemann

We consider two-loop planar contributions to a three-body form factor at the next-to-leading power in the high-energy limit, where the masses of external particles are much smaller than their energies. The calculation is performed by…

High Energy Physics - Phenomenology · Physics 2025-05-21 Yishuai Guo , Zhi-Feng Liu , Mingming Lu , Tianya Xia , Li Lin Yang

We highlight the latest developments in computing higher-order scattering amplitudes with massive internal propagators. The contributing Feynman integrals often lead to special classes of functions, for example, functions associated with…

High Energy Physics - Phenomenology · Physics 2022-07-26 Ekta Chaubey

We extend the maximal unitarity method at two loops to double-box basis integrals with up to three external massive legs. We use consistency equations based on the requirement that integrals of total derivatives vanish. We obtain unique…

High Energy Physics - Theory · Physics 2025-05-08 Henrik Johansson , David A. Kosower , Kasper J. Larsen

In this paper we continue the investigation of partition functions of critical systems on a rectangle initiated in [R. Bondesan et al, Nucl.Phys.B862:553-575,2012]. Here we develop a general formalism of rectangle boundary states using…

Mathematical Physics · Physics 2012-11-21 Roberto Bondesan , Jesper Lykke Jacobsen , Hubert Saleur