Investigation of Chiral Invariant Yukawa Models on the Lattice

The framework of the project is the investigation of Higgs-Yukawa models on the lattice which attracts special attention in view of the Higgs search at the LHC at CERN. In the past, we have computed the upper and lower mass bounds of the standard model Higgs boson using a chiral invariant lattice Higgs-Yukawa model.

In addition, we have performed a first calculation of the Higgs boson decay width at a single, perturbative value of the quartic scalar self-coupling, using finite size methods. The present project has two main goals that go beyond our past calculations. The first goal is to extend our non-perturbative computation of the Higgs boson decay width employing a number of quartic scalar self-couplings and map out the Higgs boson decay width as a function of the self-coupling, targeting also non-perturbative values. The basic idea is to apply besides the original center of mass frame a number of different moving frames in order to achieve more accurate results. The second goal is to compute lower and upper Higgs boson mass bounds for a possible heavy fourth generation of fermions. Since the fermion masses of these fourth generation quarks are expected to be of several hundred GeV, the corresponding Yukawa couplings to the Higgs field will be strong, necessitating non-perturbative lattice calculations. For both investigations we will employ chirally invariant lattice fermions realized by the Neuberger overlap operator which fulfills the Ginsparg-Wilson relation.

Müller-Preußker, Michael Prof. i. R. Dr. sc. nat. (Details) (Theoretical Physics / Theory of Elementary Particles / Phenomenology)

Financer

DFG: Sachbeihilfe

Duration of project

Start date: 05/2011

End date: 05/2014