J. Papavassiliou et A. Pilaftsis, GAUGE-GROUP-INVARIANT AND RENORMALIZATION-GROUP-INVARIANT FORMULATIONOF THE HIGGS-BOSON RESONANCE - ART. NO. 053002, Physical review. D. Particles and fields, 5805(5), 1998, pp. 3002
A gauge- and renormalization-group-invariant approach implemented by t
he pinch technique is formulated for resonant transitions involving th
e Higgs boson. The line shape of the Higgs boson is shown to consist o
f two distinct and physically meaningful contributions: a process-inde
pendent resonant part and a process-dependent non-resonant background,
which are separately gauge independent, invariant under the renormali
zation group, satisfy naive, tree-level Ward identities, and respect t
he optical and equivalence theorem individually. The former process-in
dependent quantity serves as the natural extension of the concept of t
he effective charge to the case of the Higgs scalar, and constitutes a
common ingredient of every Born-improved amplitude. The difference in
the phenomenological predictions obtained within our approach and tho
se found with other methods is briefly discussed. [S0556-2821(98)07215
-4].