Speaker
Dr
Florian Staub
(KIT)
Description
BSM models must be confronted with a series of experimental and
theoretical constraints. On the theoretical side, it is standard to
check the tree-level vacuum stability, the tree-level perturbative
unitarity constraints in the limit of large scattering energies, and
the cut-off scale using one-loop running with tree-level matching. I
will discuss that these constraints can get crucial corrections: (i)
loop corrections to the vacuum stability can re-open parameter
regions, (ii) 2 to 2 scattering at small energies can lead to much
stronger constraints, and (iii) reliable results for the high-scale
behaviour of a theory are sometimes just obtained by combining
two-loop running and matching. In addition, the check of the
perturbative behaviour of the theory can become important. Examples
for SM extensions with singlets, doublets and triplets are given.
