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Related papers: All tree-level amplitudes in massless QCD

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In this paper, we present new expressions for n-point NMHV tree-level gravity amplitudes. We introduce a method of factorization diagrams which is a simple graphical representation of R-invariants in Yang-Mills theory. We define the gravity…

High Energy Physics - Theory · Physics 2021-05-12 Jaroslav Trnka

By means of a kinematic analysis of tree level graviton amplitudes we find, at least through six points, that the reason of their decompositon as a sum over products of Yang-Mills amplitudes is on-shell gauge invariance and unitarity. As a…

High Energy Physics - Theory · Physics 2020-02-19 Luiz Antonio Barreiro , Ricardo Medina

We present new formulas for $n$-particle tree-level scattering amplitudes of six-dimensional $\mathcal{N}=(1,1)$ super Yang-Mills (SYM) and $\mathcal{N}=(2,2)$ supergravity (SUGRA). They are written as integrals over the moduli space of…

High Energy Physics - Theory · Physics 2018-10-03 Freddy Cachazo , Alfredo Guevara , Matthew Heydeman , Sebastian Mizera , John H. Schwarz , Congkao Wen

In this letter, we exploit generalised unitarity in order to calculate the cut-constructible part of one-loop amplitudes in non-supersymmetric Yang-Mills theory. In particular, we rederive the n-gluon MHV amplitudes for both the adjacent…

High Energy Physics - Phenomenology · Physics 2010-02-03 Andreas Brandhuber , Massimiliano Vincon

Witten's twistor string theory has led to new representations of S-matrix in massless QFT as a single object, including Cachazo-He-Yuan formulas in general and connected formulas in four dimensions. As a first step towards more realistic…

High Energy Physics - Theory · Physics 2017-04-05 Song He , Yong Zhang

We perform a pilot study of the perturbative renormalization of a Supersymmetric gauge theory with matter fields on the lattice. As a specific example, we consider Supersymmetric ${\cal N}{=}1$ QCD (SQCD). We study the self-energies of all…

High Energy Physics - Lattice · Physics 2017-08-16 M. Costa , H. Panagopoulos

We argue that no notion of flavour is necessary when performing amplitude calculations in perturbative QCD with massless quarks. We show this explicitly at tree-level, using a flavour recursion relation to obtain multi-flavoured QCD from…

High Energy Physics - Phenomenology · Physics 2014-10-29 Tom Melia

We review two novel techniques used to calculate tree-level scattering amplitudes efficiently: MHV diagrams, and on-shell recursion relations. For the MHV diagrams, we consider applications to tree-level amplitudes and focus in particular…

High Energy Physics - Theory · Physics 2015-05-27 Andreas Brandhuber , Bill Spence , Gabriele Travaglini

Using four-dimensional unitarity and MHV-rules we calculate the one-loop MHV amplitudes with all external particles in the adjoint representation for N=2 supersymmetric QCD with N_f fundamental flavours. We start by considering such…

High Energy Physics - Theory · Physics 2014-11-18 E. W. Nigel Glover , Valentin V. Khoze , Ciaran Williams

By applying the known expressions for SYM and SUGRA tree amplitudes, we write generating functions for the NNMHV box coefficients of SYM as well as the MHV, NMHV, and NNMHV box coefficients for SUGRA. The all-multiplicity generating…

High Energy Physics - Theory · Physics 2009-09-02 Anthony Hall

We detail the calculation of two-loop all-plus helicity amplitudes for pure Yang-Mills theory. The four dimensional unitarity methods and augmented recursion techniques we have developed, together with a knowledge of the singular structure…

High Energy Physics - Theory · Physics 2017-12-27 David C. Dunbar , John H. Godwin , Guy R. Jehu , Warren B. Perkins

We describe new on-shell recursion relations for tree-amplitudes in N=1 and N=2 gauge theories and use these to show that the structure of the S-matrix in pure N=1 and N=2 gauge theories resembles that of pure Yang-Mills. We proceed to…

High Energy Physics - Theory · Physics 2010-05-25 Shailesh Lal , Suvrat Raju

We present the fully integrated form of the two-loop four-gluon amplitude in $\mathcal{N} = 2$ supersymmetric quantum chromodynamics with gauge group SU$(N_c)$ and with $N_f$ massless supersymmetric quarks (hypermultiplets) in the…

High Energy Physics - Theory · Physics 2019-12-18 Claude Duhr , Henrik Johansson , Gregor Kälin , Gustav Mogull , Bram Verbeek

We consider the multi-collinear limit of multi-gluon QCD amplitudes at tree level. We use the MHV rules for constructing colour ordered tree amplitudes and the general collinear factorization formula to derive timelike splitting functions…

High Energy Physics - Phenomenology · Physics 2009-11-11 T. G. Birthwright , E. W. N. Glover , V. V. Khoze , P. Marquard

We present new relations for scattering amplitudes of color ordered gluons and gravitons in Einstein-Yang-Mills theory. Tree-level amplitudes of arbitrary multiplicities and polarizations involving up to three gravitons and up to two color…

High Energy Physics - Theory · Physics 2017-01-24 Dhritiman Nandan , Jan Plefka , Oliver Schlotterer , Congkao Wen

In the high-energy limit, we compute the gauge-invariant three-parton forward clusters, which in the BFKL theory constitute the tree parts of the NNLO impact factors. In the triple collinear limit, we obtain the polarized double-splitting…

High Energy Physics - Phenomenology · Physics 2008-11-26 Vittorio Del Duca , Alberto Frizzo , Fabio Maltoni

We review the structure of gauge theory scattering amplitudes at tree level and describe how a compact expression can be found which encodes all the tree-level amplitudes in the maximally supersymmetric N=4 theory. The expressions for the…

High Energy Physics - Theory · Physics 2015-05-28 J. M. Drummond

Tree-level scattering amplitudes for gravitons, gluons and Goldstone particles in any dimensions are strongly constrained by basic principles, and they are intimately related to each other via various relations. We study two types of…

High Energy Physics - Theory · Physics 2022-05-25 Jin Dong , Song He , Linghui Hou

Supersymmetric gauge theories are an important building block for extensions of the standard model. As a first step towards Super-QCD we investigate the pure gauge sector with gluons and gluinos on the lattice, in particular the low energy…

High Energy Physics - Lattice · Physics 2018-04-18 Marc Steinhauser , André Sternbeck , Björn Wellegehausen , Andreas Wipf

We review generalized unitarity as a means for obtaining loop amplitudes from on-shell tree amplitudes. The method is generally applicable to both supersymmetric and non-supersymmetric amplitudes, including non-planar contributions. Here we…

High Energy Physics - Theory · Physics 2015-05-27 Zvi Bern , Yu-tin Huang
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