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Related papers: Some Superstring Amplitude Computations with the N…

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The massless 4-point one-loop amplitude computation in the pure spinor formalism is shown to agree with the computation in the RNS formalism.

High Energy Physics - Theory · Physics 2009-11-11 Carlos R. Mafra

The open- and closed-string three- and four-point one-loop amplitudes involving massless states and one first-level massive state are computed in pure spinor superspace. For the open string, we show that their one-loop correlators can be…

High Energy Physics - Theory · Physics 2025-08-14 Carlos R. Mafra

Following suggestions of Nekrasov and Siegel, a non-minimal set of fields are added to the pure spinor formalism for the superstring. Twisted $\hat c$=3 N=2 generators are then constructed where the pure spinor BRST operator is the…

High Energy Physics - Theory · Physics 2009-11-11 Nathan Berkovits

We compute the disk amplitude of three closed strings in the pure spinor formalism. Among others, this amplitude probes tree-level gravitational interactions in the presence of Dp-branes. After disentangling holomorphic and anti-holomorphic…

High Energy Physics - Theory · Physics 2023-08-09 Andreas Bischof , Michael Haack , Stephan Stieberger

This is the first installment of a series of three papers in which we describe a method to determine higher-point correlation functions in one-loop open-superstring amplitudes from first principles. In this first part, we exploit the…

High Energy Physics - Theory · Physics 2019-09-11 Carlos R. Mafra , Oliver Schlotterer

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

The discovery of pure spinor formalism makes the computation of superstring scattering amplitudes possible. In this paper, we will illustrate how computer algebra system Cadabra is used in computing the supersymmetric amplitude in pure…

High Energy Physics - Theory · Physics 2016-08-17 Ke-Sheng Sun , Xiang-Mao Ding , Fei Sun , Hai-Bin Zhang

We give a comprehensive review of recent developments on using the pure spinor formalism to compute massless superstring scattering amplitudes at tree level. The main results of the pure spinor computations are placed into the context of…

High Energy Physics - Theory · Physics 2023-05-24 Carlos R. Mafra , Oliver Schlotterer

We develop a pure spinor worldline formalism for computing tree-level scattering amplitudes in 11D supergravity. Focusing first on the 4-point amplitude, we demonstrate that our prescription is consistent with BRST symmetry and gauge…

High Energy Physics - Theory · Physics 2025-12-11 Max Guillen , Marcelo dos Santos , Eggon Viana

The manifestly SU(4)xU(1) super-Poincare invariant free-field N=2 twistor- string action for the ten-dimensional Green-Schwarz superstring is quantized using standard BRST methods. Unlike the light-cone and semi-light-cone gauge-fixed…

High Energy Physics - Theory · Physics 2009-10-22 Nathan Berkovits

Using the pure spinor formalism we prove identities which relate the tree-level, one-loop and two-loop kinematic factors for massless four-point amplitudes. From these identities it follows that the complete supersymmetric one- and two-loop…

High Energy Physics - Theory · Physics 2014-11-18 Carlos R. Mafra

We construct the unintegrated vertex operator at the first mass level of the open superstring from the OPE of massless vertices. Using BRST cohomology manipulations, the tree amplitude of two massless and one massive state is rewritten in…

High Energy Physics - Theory · Physics 2025-03-06 Sitender Pratap Kashyap , Carlos R. Mafra , Mritunjay Verma , Luis Ypanaqué

We compute directly in covariant formalism various four point massive scalar amplitudes in bosonic string with scalars up to level 11. The most ``difficult'' amplitude we consider is four identical scalars at level 4, i.e. the first non…

High Energy Physics - Theory · Physics 2025-12-02 Igor Pesando

A manifestly super-Poincar\'e covariant formalism for the superstring has recently been constructed using a pure spinor variable. Unlike the covariant Green-Schwarz formalism, this new formalism is easily quantized with a BRST operator and…

High Energy Physics - Theory · Physics 2009-10-31 Nathan Berkovits

We present a description for amplitude diagrams in maximal supergravities obtained by dimensional reduction from D=11, derived from a field theory point of view using the pure spinor formalism. The advantages of this approach are the…

High Energy Physics - Theory · Physics 2015-06-12 Martin Cederwall , Anna Karlsson

We generalize to the eleven-dimensional superparticle Berkovits' prescription for loop computations in the pure spinor approach to covariant quantization of the superstring. Using these ten- and eleven-dimensional results, we compute…

High Energy Physics - Theory · Physics 2009-11-10 L. Anguelova , P. A. Grassi , P. Vanhove

In this paper the pure spinor formalism is used to obtain a compact expression for the superstring N-point disk amplitude. The color ordered string amplitude is given by a sum over (N-3)! super Yang-Mills subamplitudes multiplied by…

High Energy Physics - Theory · Physics 2011-06-15 Carlos R. Mafra , Oliver Schlotterer , Stephan Stieberger

The character of holomorphic functions on the space of pure spinors in ten, eleven and twelve dimensions is calculated. From this character formula, we derive in a manifestly covariant way various central charges which appear in the pure…

High Energy Physics - Theory · Physics 2009-11-11 Nathan Berkovits , Nikita Nekrasov

Explicit expressions for one-loop five supergraviton scattering amplitudes in both type II superstring theories are determined by making use of the pure spinor formalism. The type IIB amplitude can be expressed in terms of a doubling of…

High Energy Physics - Theory · Physics 2015-06-16 Michael B. Green , Carlos R. Mafra , Oliver Schlotterer

By replacing two of the bosonic scalar superfields of the N=2 string with fermionic scalar superfields (which shifts $d_{critical}$ from (2,2) to (9,1)), a quadratic action for the ten-dimensional Green-Schwarz superstring is obtained.…

High Energy Physics - Theory · Physics 2007-05-23 Nathan Berkovits