Simple examples of distinct Liouville-type symplectic structures

We discuss some examples of open manifolds which admit non-isomorphic symplectic structures of Liouville type.Comment: v2: one remark added, minor change

The Synergy between Numerical and Perturbative Approaches to Black Holes

I describe approaches to the study of black hole spacetimes via numerical relativity. After a brief review of the basic formalisms and techniques used in numerical black hole simulations, I discuss a series of calculations from axisymmetry to full 3D that can be seen as stepping stones to simulations of the full 3D coalescence of two black holes. In particular, I emphasize the interplay between perturbation theory and numerical simulation that build both confidence in present results and tools to aid and to interpret results of future simulations of black hole coalescence.Comment: 18 pages, 7 figures, To appear in "On the Black Hole Trail" eds. Bala Iyer and Biplab Bhawal (Kluwer

Model uncertainties in top-quark physics

The ATLAS and CMS collaborations at the Large Hadron Collider (LHC) are studying the top quark in pp collisions at 7 and 8 TeV. Due to the large integrated luminosity, precision measurements of production cross-sections and properties are often limited by systematic uncertainties. An overview of the modeling uncertainties for simulated events is given in this report.Comment: Proceedings from the 7th International Workshop on Top Quark Physics, Cannes, Franc

AHCAL Energy Resolution

The CALICE collaboration has constructed highly granular hadronic and electromagnetic calorimeter prototypes to evaluate technologies for the use in detector systems at a future Linear Collider. The hadron calorimeter uses 7608 small scintillator cells individually read out with silicon photomultipliers. This high granularity opens up the possibility for precise three dimensional shower reconstruction and for software compensation techniques to improve the energy resolution of the detector. We discuss the calibration procedure for the analog hadronic calorimeter and present two software compensation methods based on reconstructed clusters, which were developed with simulations and are applied to hadronic test beam data.Comment: 5 pages, 8 figures, Linear Collider Workshop 2010 Conference Proceeding

Braids and symplectic four-manifolds with abelian fundamental group

We explain how a version of Floer homology can be used as an invariant of symplectic manifolds with $b_1>0$. As a concrete example, we look at four-manifolds produced from braids by a surgery construction. The outcome shows that the invariant is nontrivial; however, it is an open question whether it is stronger than the known ones.Comment: 9 pages, LaTe

Direct Dark Matter Searches

The elucidation of the nature of dark matter is one of the challenging tasks in astroparticle physics. A brief overview on the different methods to search directly for dark matter in form of Weakly Interacting Massive Particles (WIMPs) is given.Comment: Proceedings Physics in Collision, Zeuthen, Germany, 200