Decay widths and total cross sections in perturbative QCD

Journal Article · Mon Jan 01 04:00:00 EST 1996 · Reviews of Modern Physics

DOI:https://doi.org/10.1103/RevModPhys.68.259· OSTI ID:282942

Surguladze, L R ^[1]; Samuel, M A ^[2]

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1. Department of Physics & Astronomy, University of Albama, Tuscaloosa, Alabama 35487 (United States)
2. Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

The current status of analytic higher-order perturbative computations of total cross sections and decay widths in Quantum Chromodynamics is reviewed. Important issues are the methodology of renormalization-group evaluations, the ambiguities of the renormalization scheme and its scale, and the technical challenge of calculating many-loop diagrams. As examples, the authors consider the quantities {sigma}{sub tot}({ital e}{sup +}{ital e}{sup {minus}}{r_arrow}hadrons) and {Gamma}({tau}{sup {minus}}{r_arrow}{nu}{sub {tau}}+hadrons) up to {ital O}({alpha}{sup 3}{sub {ital s}}) as well as {Gamma}({ital H}{r_arrow}hadrons) up to {ital O}({alpha}{sup 2}{sub {ital s}}). The evaluation of the four-loop QED beta function is also described. The problem of theoretical uncertainty estimates in perturbative calculations is briefly discussed. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 282942
• Journal Information: Reviews of Modern Physics, Journal Name: Reviews of Modern Physics Journal Issue: 1 Vol. 68; ISSN 0034-6861; ISSN RMPHAT
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ANNIHILATION
ELECTRON-POSITRON INTERACTIONS
PARTICLE DECAY
PERTURBATION THEORY
QUANTUM CHROMODYNAMICS
QUANTUM ELECTRODYNAMICS
RENORMALIZATION
TAU PARTICLES
TOTAL CROSS SECTIONS
WIDTH