The Construction of the CMS Silicon Strip Tracker

The CMS Silicon Strip tracker is a very large scale tracker entirely based on silicon strip detectors technology. The integration of modules, electronics, mechanics and services has been completed within the last eighteen months; first large standalone sub-structures (shells, disks, rods, petals depending on the tracker subdetector) have been integrated and verified; then they have been brought together into the final configuration. The CMS silicon tracker design and its construction is reviewed with particular emphasis on the procedures and quality checks deployed to successfully assembly several silicon strip modules and all ancillary components into these large sub-structures. An overview of the results and the lesson learned from the tracker integration are given, also in terms of failure and damage rates.Comment: 2 pages, 5 figures, submitted to Hadron Collider Physics Symposium 2007 - La Biodola (Elba) May 200

An Unexpected Effect in ALEPH: Long-Term Displacements of the Silicon Vertex Detector

The ALEPH Silicon Vertex Detector for LEP2 featured a laser survey system to monitor its mechanical stability. The analysis of laser system data from 1997 to 2000 showed that VDET suffered a time-dependent displacement. It resulted to be compatible with a deformation of the support structure that made the device to slowly rotate during the data-taking. A maximal local displacement of ~20 microns was observed, corresponding to a rotation of ~10E-4 rad. The implementation of a time-dependent correction on the alignment by using the laser system data led to sizeable improvements on the ALEPH data quality.Comment: 4 pages, 8 figures. To be published in Proceedings of 'XXXVII Rencontres de Moriond, QCD and Hadronic Interactions', March 2002, Les Arcs, Franc

The CMS Si-strip Tracker

The Compact Muon Solenoid (CMS) experiment at LHC features the largest Silicon Strip Tracker (SST) ever build. This device is immersed in a 4T magnetic field and, in conjunction with a Pixel system, it allows the momentum of the charged particles to be measured and the heavy-flavour final states to be tagged despite the hostile radiation environment. The impact of operating conditions and physics requirements on the SST layout and design choices is discussed and the expected performances are reviewed. The SST collaboration is now facing the production of the ~15000 modules and their assembly into the SST substructures. A status is given.Comment: 6 pages, 9 figures, to be published in proceedings of "8th ICATPP Conference on Astroparticle, Particle, Space Physics, Detectors and Medical Physics Applications" Como (Italy), October 200

Higgs and Beyond Standard Model Searches at LEP

Extensive searches for Higgs bosons and other new phenomena predicted by extensions of the Standard Model have been performed at LEP. A summary is given reviewing the principal aspects and presenting a selection of results.Comment: 10 pages, 7 figures, talk presented at Hadron Structure 2004, Smolenice Castle, Slovaki

SUSY Particles Searches at LEP and Interpretations within the MSSM

Searches for R-parity conserving supersymmetric particles have been performed in e+e- data collected by LEP detectors, at centre-of-mass energies up to 209GeV, corresponding to an integrated luminosity of 3.1fb-1. The results and their interpretation in the context of MSSM frameworks are briefly reviewed.Comment: 4 pages, 5 figures. To be published in Proceedings of 'ICHEP02 - 31st International Conference on High Energy Physics', 24-31 July 2002, Amsterda

CMS Inner Tracker Detector Modules

The production of silicon detector modules that will instrument the CMS Inner Tracker has nowadays reached 1300 units out of the approximately 3700 needed in total, with an overall yield close to 96%. A description of the module design, the assembly procedures and the qualification tests is given. The results of the quality assurance are presented and the experience gained is discussed.Comment: 5 pages, 3 figures, talk presented at RESMDD04, 5th International Conference on Radiation Effects on Semiconductor Materials Detectors and Devices, October 2004, Florence, Ital

The topologies of Supersymmetry signals at LEP

The topologies arising from the production of supersymmetric particles at the LEP collider are briefly reviewed recalling detector requirements, simulation and other experimental issues

Enhancement of hadron–electron discrimination in calorimeters by detection of the neutron component

In many physics experiments where calorimeters are employed, the requirement of an accurate energy measurement is accompanied by the requirement of very high hadronelectron discrimination power. Normally the latter requirement is achieved by designing a high-granularity detector with sufficient depth so that the showers can fully develop. This method has many drawbacks ranging from the high number of electronic channels to the high mass of the detector itself. Some of these drawbacks may in fact severely limit the deployment of such a detector in many experiments, most notably in space-based ones. Another method, proposed by our group and currently under investigation, relies on the use of scintillation detectors which are sensitive to the neutron component of the hadron showers. Here a review of the current status will be presented starting with the simulations performed both with GEANT4 and FLUKA. A small prototype detector has been built and has been tested in a high-energy pion/electron beam behind a "shallow" calorimeter. Results are encouraging and indicate that it is possible to enhance the discrimination power of an existing calorimeter by the addition of a small-mass neutron detector, thus paving the way for better performing astroparticle experiments. © 2010 Elsevier B.V. All rights reserved