Scintillators with Silicon Photomultiplier Readout for Timing Measurements in Hadronic Showers

The advent of silicon photomultipliers has enabled big advances in high energy physics instrumentation, for example by allowing the construction of extremely granular hadronic calorimeters with photon sensors integrated into small scintillator tiles. Direct coupling of the SiPM to the plastic scintillator, without use of wavelength shifting fibers, provides a fast detector response, making such devices well suited for precise timing measurements. We have constructed a setup consisting of 15 such scintillator tiles read out with fast digitizers with deep buffers to measure the time structure of signals in hadronic calorimeters. Specialized data reconstruction algorithms that allow the determination of the arrival time of individual photons by a detailed analysis of the recorded waveforms and that provide automatic calibration of the gain of the photon sensor, have been developed. We will discuss the experimental apparatus and the data analysis. In addition, we will report on first results obtained in a hadronic calorimeter with tungsten absorbers, providing important constraints on the time development of hadronic showers for the development of simulation models.Comment: To appear in the conference record of the IEEE Nuclear Science Symposium and Medical Imaging Conference, Valencia, Spain, October 201

Standard Model Higgs Searches and Perspectives at the Tevatron

The status and perspectives of Standard Model Higgs searches at the Tevatron experiments CDF and D0 are discussed.Comment: 7 pages, 3 figures, submitted to proceedings of Les Rencontres de Physique de la Vallee d'Aoste, Italy, 5-11 March 200

Jet Production in Photon-Photon Interactions

The inclusive one- and two-jet cross-sections are measured in collisions of quasi-real photons at e+e- centre-of-mass energies of 130 and 136 GeV using the OPAL detector at LEP. Jets are reconstructed with a cone jet finding algorithm. The jet cross-sections are compared to next-to-leading order (NLO) perturbative QCD calculations. Transverse energy flows in jets are studied separately for direct and resolved two-photon events.Comment: 4 pages, 6 Postscript figures, uses stwol.st

Photon Structure

The structure of the photon is probed in photon-photon interactions at LEP and in photon-proton interactions at HERA.Comment: 10 pages, submitted to proceedings of DIS2000, Liverpool, UK, 25-30 April 200

Standard Model Higgs Searches

The status and perspectives of Standard Model Higgs searches are discussed.Comment: submitted to Proceedings of Lepton-Photon 2007, 13-18 August 2007, Daegu, Kore

Experimental Status of Leptonic Ds Decays

The measurements of the leptonic branching ratios BR(Ds->tau nu) and BR(Ds->mu nu) are reviewed. The values of the Ds decay constant fDs derived from the measurements are updated and a world average is calculated taking into account the large correlations between the measurementsComment: 6 pages,1 figure, EPS 2001 Budapes