English
Related papers

Related papers: Automatic one-loop calculation of MSSM processes w…

200 papers

We present the program package GoSam which is designed for the automated calculation of one-loop amplitudes for multi-particle processes in renormalisable quantum field theories. The amplitudes, which are generated in terms of Feynman…

Using the automatic system GRACE-LOOP, the full $O(\alpha)$ electroweak corrections has been calculated for the process $e^+e^- \to W^+\mu \bar{\nu}_{\mu}$. The total correction to the cross section is found to be typically -6.4% at…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Fujimoto , T. Ishikawa , Y. Kurihara , Y. Shimizu , K. Kato , N. Nakazawa , T. Kaneko

The complete tree level cross section for the process $e^+e^- \to e^- \bar\nu_e u \bar{d}$ is computed using the GRACE system, a program package for automatic amplitude calculation. Special attention is brought to the gauge violation…

High Energy Physics - Phenomenology · Physics 2009-10-28 Y. Kurihara , D. Perret-Gallix , Y. Shimizu

In the paper we recalculate and discuss high-precision theoretical predictions for cross sections of the process $e^+e^- \to Z Z$. We assume a complete one-loop implementation and a possibility of estimating the initial state polarizations,…

High Energy Physics - Phenomenology · Physics 2024-01-25 S. Bondarenko , Ya. Dydyshka , L. Kalinovskaya , R. Sadykov , V. Yermolchyk

In this talk, the program package GOSAM is presented, which can be used for the automated calculation of one-loop amplitudes for multi-particle processes. The integrands are generated in terms of Feynman diagrams and can be reduced by…

High Energy Physics - Phenomenology · Physics 2012-01-19 G. Cullen , N. Greiner , G. Heinrich , G. Luisoni , P. Mastrolia , G. Ossola , T. Reiter , F. Tramontano

A general non-linear gauge condition is implemented into GRACE, an automated system for the calculation of physical processes in high-energy physics. This new gauge-fixing is used as a very efficient means to check the results of large…

High Energy Physics - Phenomenology · Physics 2019-08-17 G. Belanger , F. Boudjema , J. Fujimoto , T. Ishikawa , T. Kaneko , K. Kato , V. Lafage , N. Nakazawa , Y. Shimizu

We have been developing a program package called GRACE/SUSY-loop which automatically calculates the MSSM amplitudes in one-loop order. We present numerical results of calculations for pair-production and three-body decay of the lighter stop…

High Energy Physics - Phenomenology · Physics 2012-02-29 M. Jimbo , T. Inoue , T. Jujo , T. Kon , T. Ishikawa , Y. Kurihara , K. Kato , M. Kuroda

The program package GoSam is presented which aims at the automated calculation of one-loop amplitudes for multi-particle processes. The amplitudes are generated in terms of Feynman diagrams and can be reduced using either D-dimensional…

High Energy Physics - Phenomenology · Physics 2015-06-03 G. Cullen , N. Greiner , G. Heinrich , G. Luisoni , P. Mastrolia , G. Ossola , T. Reiter , F. Tramontano

We study the process $e^-e^+\to ZH$ where $H$ represents the standard model (SM) Higgs particle $H_{SM}$, or the MSSM ones $h^0$ and $H^0$. In each case, we compute the one-loop effects and establish very simple expressions, called…

High Energy Physics - Phenomenology · Physics 2015-06-22 G. J. Gounaris , F. M. Renard

We present GoSam 2.0, a fully automated framework for the generation and evaluation of one loop amplitudes in multi leg processes. The new version offers numerous improvements both on generational aspects as well as on the reduction side.…

High Energy Physics - Phenomenology · Physics 2014-10-14 Nicolas Greiner

For the search for electroweak (EW) particles in the Minimal Supersymmetric Standard Model (MSSM) as well as for future precision analyses of these particles an accurate knowledge of their production and decay properties is mandatory. We…

High Energy Physics - Phenomenology · Physics 2018-07-12 S. Heinemeyer , C. Schappacher

\susy23 is a Monte-Carlo package for generating supersymmetric (SUSY) processes at $e^+e^-$ colliders. Twenty-three types of SUSY processes with 2 or 3 final state particles at tree level are included in version 2.0. {\susy23} addresses…

High Energy Physics - Phenomenology · Physics 2016-09-06 J. Fujimoto , K. Hikasa , T. Ishikawa , M. Jimbo , T. Kaneko , K. Kato , S. Kawabata , T. Kon , M. Kuroda , Y. Kurihara , T. Munehisa , D. Perret-Gallix , Y. Shimizu , H. Tanaka

In this presentation, we describe the GoSam (Golem/Samurai) framework for the automated computation of multi-particle scattering amplitudes at the one-loop level. The amplitudes are generated analytically in terms of Feynman diagrams, and…

Two methods to reduce the CPU time needed for the numerical evaluation of cross-sections and similar quantities are discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Hahn

By using the GRACE-Loop system, we calculate the full $\mathcal{O}(\alpha)$ electroweak radiative corrections to the process $e^+e^- \rightarrow e^+e^- \gamma$, which is important for future investigations at the International Linear…

High Energy Physics - Phenomenology · Physics 2014-12-08 P. H. Khiem , Y. Kurihara , J. Fujimoto , T. Ishikawa , T. Kaneko , K. Kato , N. Nakazawa , Y. Shimizu , T. Ueda , J. A. M. Vermaseren , Y. Yasui

We study the process $e^-e^+\to \gamma H$, where $H$ represents $H_{SM}$, $h^0$ or $H^0$, which occurs at the one loop level in the standard model (SM) or in the minimal supersymmetric standard model (MSSM). We establish supersimple (sim)…

High Energy Physics - Phenomenology · Physics 2015-05-13 G. J. Gounaris , F. M. Renard

We review recent progress towards automated higher-order calculations in the MSSM with complex parameters (cMSSM). The consistent renormalization of all relevant sectors of the cMSSM and the inclusion into the FeynArts/FormCalc framework…

High Energy Physics - Phenomenology · Physics 2014-07-02 T. Hahn , S. Heinemeyer , F. von der Pahlen , H. Rzehak , C. Schappacher

We present a semi-numerical method to compute one-loop corrections to processes involving many particles. We treat in detail cases with up to five external legs and massless internal propagators, although the method is more general.

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Zanderighi

In this talk we review the GOLEM approach to one-loop calculations and present an automated implementation of this technique. This method is based on Feynman diagrams and an advanced reduction of one-loop tensor integrals which avoids…

We discuss one-loop contributions of supersymmetry (SUSY) particles to the process $e^+e^- \to W^+W^-$ in the minimal supersymmetric standard model. The calculation is tested by using the sum rule among the form factors, which is based on…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kaoru Hagiwara , Shinya Kanemura , Yoshiaki Umeda