1. 4 th Generation Leptons in Minimal Walking Technicolor Theory Matti Heikinheimo University of Jyväskylä

2. Background: What is technicolor? In SM, electroweak symmetry is broken by the Higgs field Hierarchy problem: Solution: Break electroweak symmetry dynamically Technicolor = a new strongly interacting sector accounts for EWSB

3. Walking Technicolor To get SM fermion masses, we need another new interaction at some high scale This gives four-fermion vertices between SM fermions and techniquarks → Flavour changing neutral currents Need walking dynamics to suppress the FCNCs

4. Walking behaviour of the coupling constant as a function of momentum

5. Minimal Walking Technicolor Model Fundamental techniquarks: needed for walking → Too large contributions to the S parameter Adjoint techniquarks → Need only

6. New particles:,, in the adjoint representation of We have added three new weak doublets → the model suffers from Witten anomaly Cure the anomaly: add one more weak doublet → 4 th lepton generation,, Neutrino mass matrix allows the neutrino to have a general mass structure → Two Majorana neutrinos,

7. Phenomenology of the 4 th generation leptons The phenomenology of the 4 th lepton generation has been studied, but usually with 4 th QCD quark generation MWTC adds only the 4 th generation leptons but no QCD quarks We also allow the new neutrino to have a general mass structure

8. The Lagrangian: where, and mass matrix eigenvalues → Mass eigenstates, where Neutral current Charged current

17. Decay fractions of the Higgs boson in the standard model and in MWTC