Effective charges and expansion parameters in QCD

The momentum subtraction scheme MOM has been empirically successful in producing small QCD corrections to physical quantities at one loop order. By explicit calculations, we show that with a suitable shift in the renormalization scale, the minimal subtraction scheme coupling constant αMS coincides with typical momentum scheme coupling constants at both one and two loop order.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87888/2/107_1.pd