Report on the seismic performance of three-dimensional moment-resisting timber frames with frictional damping in beam-to-column connections

The seismic performance of three-dimensional moment-resisting timber frames with frictional damping devices was investigated experimentally. This article describes a novel three-dimensional beam-to-column connection which was designed to behave rigidly up to moderate seismic intensities and to start the frictional dissipating behavior at higher intensities. The three-dimensional beam-to-column connection component was initially tested under cyclic loading, and then the connection was mounted in a three-level prototype frame and tested on a shake table. From the cyclic loading tests, the energy dissipation of the proposed beam-to-column connection was higher than the equivalent rigid connection. The frame demonstrated self-aligning capabilities without permanent drift at seismic intensities up to 1.4 g and maintained strength up to high seismic intensities of 2 g. Because wood frames allow for large elastic deflections and can exhibit excellent self-aligning capabilities (i.e., connections tolerate large rotations within safe stress levels), the proposed frictional beam-to-column connection is a promising alternative for moment-resisting timber frames that can be used to prevent structural members from reaching critical stresses

First results and future perspectives of the NA60 experiment

The NA60 experiment at the CERN SPS studies the production of open charm and prompt dimuons in collisions induced by proton and heavy ion beams on nuclear targets. The experimental setup includes a silicon vertex telescope, placed inside a dipole magnetic field, to match charged particle tracks with the muon tracks measured by a muon spectrometer. In p-A collisions the vertex telescope is mostly made of silicon microstrip planes, whereas in A-A interactions the higher multiplicity imposes the use of high granularity silicon pixel detectors. The high interaction rate required for the study of rare processes imposes the use of radiation tolerant pixel detectors. NA60 took its first data in the year 2002, with 400 GeV protons and with Pb ions of 20 and 30 GeV per nucleon. The proton data have been used for the study of dimuon production, while the heavy ion data were devoted to the commissioning of the pixel detectors and to the study of charged particle pseudorapidity densities. After an overview of the detector concept, this paper presents the first results obtained with the 2002 data. (4 refs)

The NA60 experiment at CERN SPS: first results and prospects

The NA60 experiment is taking place at the CERN SPS, to study the production of open charm and of prompt dimuons in collisions induced by proton and heavy ion beams on nuclear targets. In this paper we will present an overview of the detector concept, followed by a description of the newly developed silicon vertex telescope and its performance. Then we present some first results, including a dimuon mass spectrum obtained using the silicon vertex telescope