Stefan Dittmaier - Renormalization of extended Higgs sectors
→
Europe/Rome
248 (Ed. C primo piano)
248
Ed. C primo piano
Description
In the Standard Model (SM) of particle physics, ElectroWeak Symmetry Breaking
(EWSB) is described by the Higgs mechanism which predicts one scalar degree
of freedom - the Higgs boson - in its minimal form. Almost all theories for
physics beyond the SM predict either modifications or extensions of this
scalar sector, so that its phenomenological investigation at the LHC or
at future colliders might serve as door opener to the discovery of new
particles, structures, or underlying symmetries.
Simple extensions of the scalar sector, such as the Two-Higgs-Doublet Model
(THDM) or Singlet Extensions of the SM (SESM), generically reflect features
of EWSB of more comprehensive theories, but still have the advantage to
allow for precise perturbative predictions as renormalizable quantum field
theories (QFTs). Although the advanced concepts and techniques of perturbative
QFT still apply to such models, new issues arise in the new sectors, such as
the question about phenomenoligically sound renormalization and input-parameter
schemes, which fulfill desirable theoretical requirements (gauge invariance,
perturbative stability, symmetries, simplicity, etc.), which are prerequisites
for a confrontation of theory and experiment at the precision level.
In this talk these issues are discussed at some general level and exemplified
for the THDM and the SESM in particular. Old and new renormalization schemes
are discussed and illustrated in applications to some Higgs-boson production
and decay processes.
