A Large TPC Prototype with MPGD Readout: Status and Plans

The use of a TPC in future collider experiments needs significant research and development. Within the EUDET program an infrastructure has been designed and built to allow the efficient testing of TPC prototypes under realistic conditions. The infrastructure consists of a test beam facility, located at DESY Hamburg, and a multi-purpose TPC field cage.Comment: Conference LCES 2008, Chicag

Reduced density-matrix functionals applied to the Hubbard dimer

Common density-matrix functionals, the M\"uller and the power functional, have been benchmarked for the half-filled Hubbard dimer, which allows to model the bond dissociation problem and the transition from the weakly to the strongly correlated limit. Unbiased numerical calculations are combined with analytical results. Despite the well known successes of the M\"uller functional, the ground state is degenerate with a one-dimensional manifold of ferromagnetic solutions. The resulting infinite magnetic susceptibility indicates another qualitative flaw of M\"uller's functional. The derivative discontinuity with respect to particle number is not present indicating an incorrect metal-like behavior. The power functional actually favors the ferromagnetic state for weak interaction. Analogous to the Hartree-Fock approximation, the power functional undergoes a transition beyond a critical interaction strength, in this case however, to a non-collinear antiferromagnetic state.Comment: 17 pages, 16 figure

A Lightweight Field Cage for a Large TPC Prototype for the ILC

We have developed and constructed the field cage of a prototype Time Projection Chamber for research and development studies for a detector at the International Linear Collider. This prototype has an inner diameter of 72 cm and a length of 61 cm. The design of the field cage wall was optimized for a low material budget of 1.21 % of a radiation length and a drift field homogeneity of Delta(E)/(E) less or equal 10^-4. Since November 2008 the prototype has been part of a comprehensive test beam setup at DESY and used as a test chamber for the development of Micro Pattern Gas Detector based readout devices.Comment: 16 pages, 13 figures, 3 table

Low-probability insurance decisions: The role of concern

On the basis of a real high stakes insurance experiment with small probabilities of losses, we demonstrate that concern is a more important driver of WTP for insurance than subjective probability estimates when there is ambiguity surrounding the estimate. Concern is still important when probabilities are exactly given. It also helps explaining the low probability insurance puzzle well known from the literature, where a part of individuals pays too much and a part nothing for coverage, a result we are able to replicate. In our experiment, belonging to either the group of threshold persons or to those that pay far too much, is not related to probability judgments but to the degree an individual is concerned in our decision situation

Technology Learning Curves for Energy Policy Support

The European Commission's Joint Research Centre and the Energy Research Centre of the Netherlands (ECN) organised an expert workshop on 'Learning Curves for Policy Support' in Amsterdam on 8 March 2012. It aimed to assess the challenges in the application of the two-factor learning curve, or alternative solutions in supporting policy decision making in the framework of the European Strategic Energy Technology Plan, and explored options for improvement. The workshop gathered distinguished experts in the field of scientific research on learning curves and policy researchers from the European Commission and ECN to assess the challenges in the application of the two-factor-learning curve, or alternative solutions in supporting policy decision making, and to provide options for improvement. This paper forms the summary of outcomes from the workshop. Due to the very different nature of the One-Factor-Learning concept and the Two-Factor-Learning concept, these are discussed in separate parts. In each of these parts the context and the methodology are introduced, methodological and data challenges are described and the problems associated with the application of the concept in models is discussed.JRC.F.6-Energy systems evaluatio

A Time Projection Chamber with GEM-Based Readout

For the International Large Detector concept at the planned International Linear Collider, the use of time projection chambers (TPC) with micro-pattern gas detector readout as the main tracking detector is investigated. In this paper, results from a prototype TPC, placed in a 1 T solenoidal field and read out with three independent GEM-based readout modules, are reported. The TPC was exposed to a 6 GeV electron beam at the DESY II synchrotron. The efficiency for reconstructing hits, the measurement of the drift velocity, the space point resolution and the control of field inhomogeneities are presented.Comment: 22 pages, 19 figure

BIOMECHANICAL ANALYSIS OF THE POLE VAULT

INTRODUCTION: The main purposes of this study were to (a) examine the behavior and practical application of 3 criteria in world class pole vaulters and (b) to determine the influence of the starting conditions and athlete's behavior during the pole phase, on performance. Note that the three criteria label the starting conditions of the pole vault and the behavior of athletes during the pole phase. METHODS: Data for this study were gathered at the 1997 Track and Field World Championships in Athens, Greece. Twenty-five successful jumps by 11 participants in the final competition were analyzed. The data for the two-dimensional analysis were recorded using two synchronized stationary video cameras operating at 50 Hz. For the analysis of the data, the pole vault was divided into (a) energy production phase (This phase begins with the approach and ends with the contact of the jump foot and the ground at take-off.) and (b) energy exchange phase (This phase begins with contact of the jump foot and the ground at take-off and ends when the athlete releases the pole at the end of the jump.). RESULTS AND CONCLUSIONS: During the first part of the energy exchange phase, energy is transferred into the pole, reducing the athlete's total energy. The difference between the decrease of the athlete's total energy and the maximum pole energy indicates whether pole elasticity was effectively used (Criterion 1) (see Figure 1). During the second part of the energy exchange phase, the energy is transferred back from the pole to the athlete, increasing the athlete's total energy. The difference between the returned energy and the energy gain of the athlete indicates to what extent the athlete used muscular work to create additional energy (Criterion 2). The approach energy (start energy) represents the starting conditions of the pole vaulter (Criterion 3). From the analyzed jumps, it was possible to create 3 groups which demonstrated similar values for start energy, Criterion 1 and Criterion 2. The results indicate that both individual and group-specific technique deficits of athletes can vary and still produce the same performance. At the elite level, the start energy determines the beginning conditions for good or poor jump performance. The actual jump heights achieved are dependent on the behavior of the vaulter during the energy exchange phase. From the examination of the start energy, Criterion 1 and Criterion 2, it was possible to diagnose the individual technical deficits of the athletes