Supersymmetry

The determination of supersymmetric parameters at the LHC in favorable as well as difficult scenarios is presented. If discovered and measured at the LHC and the ILC, supersymmetry may provide a link between collider physics and cosmology.Comment: Invited talk at XVII International Workshop on Deep-Inelastic Scattering and Related Subjects DIS 2009, 26-30 April 2009, Madrid. 5 pages, 5 figure

Measuring Hidden Higgs and Strongly-Interacting Higgs Scenarios

Higgs couplings can be affected by physics beyond the Standard Model. We study modifications through interactions with a hidden sector and in specific composite Higgs models accessible at the LHC. Both scenarios give rise to congruent patterns of universal, or partially universal, shifts. In addition, Higgs decays to the hidden sector may lead to invisible decay modes which we also exploit. Experimental bounds on such potential modifications will measure the concordance of an observed Higgs boson with the Standard Model.Comment: 12 pages, 7 figures; version to be published in Phys. Lett.

Electroweak Symmetry Breaking and Higgs Physics

An introduction to electroweak symmetry breaking and Higgs physics is presented for the Standard Model and its supersymmetric extensions. A brief overview will also be given on strong interactions of the electroweak gauge bosons in alternative scenarios. In addition to the theoretical basis, the present experimental status of Higgs physics and implications for future experiments at the LHC and $e^+e^-$ linear colliders are discussed.Comment: 70 pages, latex, 30 figure

Doubly Charged Higgsino Pair Production and Decays in e+e- Collisions

In supersymmetric grand unified theories, light higgsino multiplets generally exist in addition to the familiar chargino/neutralino multiplets of the minimal supersymmetric extension of the Standard Model. The new multiplets may include doubly charged states $\tilde\Delta^{\pm\pm}$ and $\tilde\delta^{\pm\pm}$. We study the properties and the production channels of these novel higgsinos in $e^+e^-$ and $\gamma\gamma$ collisions, and investigate how their properties can be analyzed experimentally.Comment: LATEX, 25 pages, ps figures include

SUSY parameter determination

The impact of the LHC, SLHC and the ILC on the precision of the determination of supersymmetric parameters is investigated. In particular, in the point SPS1a the measurements performed at the ILC will improve by an order of magnitude the precision obtained by the LHC alone. The SLHC with respect to the LHC has the potential to reduce the errors by a factor two.Comment: Invited talk at 2005 International Linear Collider Physics and Detector Workshop and Second ILC Accelerator Workshop, Snowmass, CO(Snowmass05) 3 pages, LaTe

SFITTER: SUSY Parameter Analysis at LHC and LC

SFITTER is a new analysis tool to determine supersymmetric model parameters from collider measurements. Using the set of supersymmetric mass measurements at the LC and at the LHC we show how both colliders probe different sectors of the MSSM Lagrangian. This observation is a strong motivation to move from a parameter fit assuming a certain model to the unconstrained weak-scale MSSM Lagrangian. We argue how the technical challenges can be dealt with in a combined fit/grid approach with full correlations.Comment: contribution to LHC-LC Study Group, G.Weiglein et a

Extraction of SUSY Parameters from Collider Data

The extraction of the parameters of the supersymmetric Lagrangian is discusse d. Particular emphasis is put on the rigorous treatment of experimental and theo retical errors. While the LHC can provide a valuable first estimate of the parameters, the combination of LHC and ILC will be nece ssary to determine with high precision the parameters of the MSSM.Comment: 6 pages, 4 figures, Proceedings of plenary talk at SUSY08 in Seoul, Korea (typos corrected

Gluon Fragmentation to Gluonium

The fragmentation of gluons to gluonium states is analyzed qualitatively in the non-perturbative region. The convolution of this mechanism with perturbative gluon radiation leaves us with a hard component in the fragmentation of gluon to gluonium.Comment: 6 pages with 2 figures, LaTe