Direct extraction of one-loop integral coefficients
Creators
- 1. Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309, USA and Department of Physics and Astronomy, UCLA, Los Angeles, California 90095-1547 (United States)
Description
We present a general procedure for obtaining the coefficients of the scalar bubble and triangle integral functions of one-loop amplitudes. Coefficients are extracted by considering two-particle and triple unitarity cuts of the corresponding bubble and triangle integral functions. After choosing a specific parametrization of the cut loop momentum we can uniquely identify the coefficients of the desired integral functions simply by examining the behavior of the cut integrand as the unconstrained parameters of the cut loop momentum approach infinity. In this way we can produce compact forms for scalar integral coefficients. Applications of this method are presented for both QCD and electroweak processes, including an alternative form for the recently computed three-mass triangle coefficient in the six-photon amplitude A6(1-,2+,3-,4+,5-,6+). The direct nature of this extraction procedure allows for a very straightforward automation of the procedure
Additional details
Identifiers
- DOI
- 10.1103/PhysRevD.75.125019;
- arXiv
- arXiv:0704.1835v1;
Publishing Information
- Journal Title
- Physical Review. D, Particles Fields
- Journal Volume
- 75
- Journal Issue
- 12
- Journal Page Range
- p. 125019-125019.20
- ISSN
- 0556-2821
- CODEN
- PRVDAQ
INIS
- Country of Publication
- United States
- Country of Input or Organization
- International Atomic Energy Agency (IAEA)
- INIS RN
- 38090854
- Subject category
- S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
- Descriptors DEI
- EXTRACTION; FUNCTIONS; INTEGRALS; MASS; PHOTONS; QUANTUM CHROMODYNAMICS; SCALARS; UNITARITY
- Descriptors DEC
- BOSONS; ELEMENTARY PARTICLES; FIELD THEORIES; MASSLESS PARTICLES; QUANTUM FIELD THEORY; SEPARATION PROCESSES
Optional Information
- Notes
- (c) 2007 The American Physical Society