Abstract
We discuss the new model expression recently obtained for the QCD running coupling with a regular ghost-free behavior in the “low ” region. Being deduced from the standard “asymptotic-freedom” expression by imposing the analyticity—without any adjustable parameters—it has nice features: (i) The universal limiting value expressed only via group symmetry factors and independent of experimental estimates on the running coupling (of QCD scale parameter ). This value is stable with respect to higher order corrections. (ii) Stability of IR behavior with respect to higher-loop effects. (iii) Coherence between the experimental value and integral information on IR behavior as extracted from jet physics data.
- Received 28 October 1996
DOI:https://doi.org/10.1103/PhysRevLett.79.1209
©1997 American Physical Society