Exploring Higgs Sector Spectroscopy

The Higgs sector of the standard model is field-theoretically a very interesting theory. Because strong and weak coupling domains are continuously connected, only quantitative changes distinguish the various regions. Especially, this is true for the asymptotic spectrum, which can only consist out of gauge-invariant composite, i. e. bound, states. Since in some regions of parameter space even Regge trajectories are expected to exist, there is immediately the possibility that resonances may also be present in the parameter region characteristic of the standard model Higgs sector. This possibility is discussed in some detail, starting from the definition of the theory to spectroscopy, including excited state analysis, to some considerations whether this could have experimental consequences. The strongest limitation for this exploration turns out to be that the gauge coupling without fermions runs much faster, and the gauge sector is therefore potentially affected.Comment: 7 pages, 4 figures, talk given at the "XXXI International Symposium on Lattice Field Theory", Mainz, July/August 2013. Submitted to the proceeding

Two- and three-point functions in Landau gauge Yang-Mills-Higgs theory

Yang-Mills-Higgs theory offers a rich set of physics. In particular, in some region of its parameter space it has QCD-like behavior, while in some other range it is Higgs-like. Furthermore, for the choice of the gauge group SU(2) and an SU(2) Higgs flavor symmetry it is the Higgs sector of the standard model. Therefore, it is possible to study a plethora of phenomena within a single theory. Here the standard-model version is studied using lattice gauge theory. Choosing non-aligned minimal Landau gauge, its propagators and three-point vertices will be determined in both the QCD-like and Higgs-like domains. This permits to test various proposals for how confinement works, as well as how confinement and the Higgs effect differ. The correlations functions are found to exhibit a different behavior, depending on whether the lowest mass scalar flavor singlet is lighter than the vector triplet, heavier and stable, or unstable against decay into two vector triplets.Comment: 46 pages, 22 figures, 1 table v2: Some pictures updated with more statistics, minor changes, one paragraph on 4-point functions added, version accepted by JHE

Correlation Functions and Confinement in Scalar QCD

The complete knowledge of a theory is encoded in its correlation functions. Thus non-perturbative effects, like confinement in QCD, is necessarily contained in these correlation functions. As a consequence, a number of confinement scenarios make predictions for the behavior of these correlation functions. Non-perturbative methods, like lattice calculations, permit to calculate the correlation functions and test these predictions. To avoid the entanglement with chiral symmetry breaking and the costs of full fermion simulations, here scalar QCD will be used as a role model, as it is expected that confinement operates in the same way. We present results on both two-point functions and three-point functions for the case of two colors and two flavors of scalars, and compare them to the predictions.Comment: 7 pages, 6 figures, combined proceeding for the conferences EPSHEP 2013 Stockholm, Sweden, July 2013, XXXI International Symposium on Lattice Field Theory", Mainz, July/August 2013, and QCD TNT3, Trento, September 201