Gauge coupling constant, compositeness and supersymmetry
  We point out the possibility that the magnitude of the bare gauge coupling constant is determined theoretically in a composite model of all particles in SUSY theories. We show explicitly in two space-time dimensions that the NL/L SUSY relation (i.e., a SUSY compositeness condition for all particles) between N = 2 LSUSY QED and N = 2 NLSUSY determines the magnitude of the bare electromagnetic coupling constant (i.e., the fine structure constant) of N = 2 LSUSY QED. 
Kazunari Shima and Motomu Tsuda