"Massive" Perturbative QCD, regular in the IR limit

Understand

The goal of research is to devise a modification of the perturbative QCD that should be regular in the low-energy region and could serve as a practical means for the analysis of data below 1 \GeV up to the IR limit.

• Recent observation of the four-loop pQCD series "blow-up" in the region below 1 \GeV for the Bjorken Sum Rule gave an impetus to this attempt.
• The proposed {\sf "massive analytic pQCD"} is constructed on the two grounds.
• The first is the pQCD with only one parameter added, the effective "glueball mass" $m_{gl}\lesssim 1 \GeV,$ serving as an IR regulator.