Bootstrapping multiparton loop amplitudes in QCD

Journal Article · Wed Mar 15 00:00:00 EST 2006 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.73.065013· OSTI ID:20782684

Bern, Zvi ^[1]; Dixon, Lance J ^[2]; Kosower, David A ^[3]

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1. Department of Physics and Astronomy, UCLA, Los Angeles, California 90095 (United States)
2. Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)
3. Service de Physique Theorique, CEA-Saclay, F-91191 Gif-sur-Yvette cedex (France)

We present a new method for computing complete one-loop amplitudes, including their rational parts, in nonsupersymmetric gauge theory. This method merges the unitarity method with on-shell recursion relations. It systematizes a unitarity-factorization bootstrap approach previously applied by the authors to the one-loop amplitudes required for next-to-leading order QCD corrections to the processes e{sup +}e{sup -}{yields}Z,{gamma}{sup *}{yields}4 jets and pp{yields}W+2 jets. We illustrate the method by reproducing the one-loop color-ordered five-gluon helicity amplitudes in QCD that interfere with the tree amplitude, namely A{sub 5;1}(1{sup -},2{sup -},3{sup +},4{sup +},5{sup +}) and A{sub 5;1}(1{sup -},2{sup +},3{sup -},4{sup +},5{sup +}). Then we describe the construction of the six- and seven-gluon amplitudes with two adjacent negative-helicity gluons, A{sub 6;1}(1{sup -},2{sup -},3{sup +},4{sup +},5{sup +},6{sup +}) and A{sub 7;1}(1{sup -},2{sup -},3{sup +},4{sup +},5{sup +},6{sup +},7{sup +}), which uses the previously-computed logarithmic parts of the amplitudes as input. We present a compact expression for the six-gluon amplitude. No loop integrals are required to obtain the rational parts.

• OSTI ID: 20782684
• Journal Information: Physical Review. D, Particles Fields, Vol. 73, Issue 6; Other Information: DOI: 10.1103/PhysRevD.73.065013; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
COLOR MODEL
CORRECTIONS
ELECTRON-POSITRON INTERACTIONS
FACTORIZATION
GAUGE INVARIANCE
GLUONS
HELICITY
INCLUSIVE INTERACTIONS
JET MODEL
PROTON-PROTON INTERACTIONS
QUANTUM CHROMODYNAMICS
RECURSION RELATIONS
UNITARITY
UNITARY SYMMETRY
W MINUS BOSONS
W PLUS BOSONS
Z NEUTRAL BOSONS