Publications (12)
Numerical Evaluation of Feynman Integrals by a Direct Computation Method
F. Yuasa, T. Ishikawa, J. Fujimoto +3
A purely numerical method, Direct ComputationMethod is applied to evaluate Feynman integrals. This method is based on the combination of an efficient numerical integration and an e…
Precise Numerical Evaluation of the Scalar One-Loop Integrals with the Infrared Divergence
F. Yuasa, E. de Doncker, J. Fujimoto +3
We present a new approach for obtaining very precise integration results for infrared vertex and box diagrams, where the integration is carried out directly without performing any…
Numerical Approach to Calculation of Feynman Loop Integrals
F. Yuasa, T. Ishikawa, Y. Kurihara +5
In this paper, we describe a numerical approach to evaluate Feynman loop integrals. In this approach the key technique is a combination of a numerical integration method and a nume…
Automatic Computation of Cross Sections in HEP
F. Yuasa, J. Fujimoto, T. Ishikawa +10
For the study of reactions in High Energy Physics (HEP) automatic computation systems have been developed and are widely used nowadays. GRACE is one of such systems and it has achi…
Status reports from the GRACE Group
Y. Yasui, T. Ueda, E. de Doncker +5
We discuss a new approach for the numerical evaluation of loop integrals. The fully numerical calculations of an infrared one-loop vertex and a box diagram are demonstrated. To per…
Recent Developments in Parallelization of the Multidimensional Integration Package DICE
F. Yuasa, K. Tobimatsu, S. Kawabata
DICE is a general purpose multidimensional numerical integration package. There can be two ways in the parallelization of DICE, "distributing random numbers into workers" and "dist…
A Feynman graph selection tool in GRACE system
F. Yuasa, T. Kaneko, T. Ishikawa
We present a Feynman graph selection tool {\tt grcsel}, which is an interpreter written in C language. In the framework of {\tt GRACE}, it enables us to get a subset of Feynman gra…
Regularization with Numerical Extrapolation for Finite and UV-Divergent Multi-loop Integrals
E. de Doncker, F. Yuasa, K. Kato +3
We give numerical integration results for Feynman loop diagrams such as those covered by Laporta [1] and by Baikov and Chetyrkin [2], and which may give rise to loop integrals with…
Numerical approach to multi-loop integrals
K. Kato, E. de Doncker, N. Hamaguchi +5
For the calculation of multi-loop Feynman integrals, a novel numerical method, the Direct Computation Method (DCM) is developed. It is a combination of a numerical integration and…
Numerical Computation of Two-loop Box Diagrams with Masses
F. Yuasa, E. de Doncker, N. Hamaguchi +5
A new approach is presented to evaluate multi-loop integrals, which appear in the calculation of cross-sections in high-energy physics. It relies on a fully numerical method and is…
with a production
F. Yuasa, Y. Kurihara, S. Kawabata
The cross section of process with a complete set of tree diagrams, 232 diagrams in the unitary gauge, was calculated at the energy r…
Loop integration results using numerical extrapolation for a non-scalar integral
E. de Doncker, Y. Shimizu, J. Fujimoto +4
Loop integration results have been obtained using numerical integration and extrapolation. An extrapolation to the limit is performed with respect to a parameter in the integrand w…