F. Bosi

Double-sided readout silicon strip detectors for the aleph minivertex

Abstract Large double-sided readout silicon strip detectors have been fabricated for the Aleph minivertex. We have tested them with a β-source and have observed charge collection and capacitive charge division both on the junction side and on the ohmic side. A charge correlation has been observed between the two faces and can be used to reduce ambiguities in the case of two particles crossing the same wafer.

Performance of the UA2 jet vertex detector at the CERN collider

Abstract The UA2 jet vertex detector, a drift chamber with jet geometry, was successfully operated during the 1987 and 1988 CERN pp Collider runs. A description of the chamber and a comparison between test-beam results and the chambers performance during the Collider runs are given.

A modular drift-chamber vertex detector at the CERN ISR

Abstract The vertex detector built by the Pisa Group for the CERN Intersecting Storage Rings muon pair experiment R 209 is described. A modular system of 136 small drift chambers, assembled around the ISR intersection region, measures the entrance directions of the muon pairs into the magnetized iron spectrometer, and the directions of the charged hadrons produced in association. Each module contains two doublets of sense wires, each doublet being associated with one delay line to determine directly the space points without left-right ambiguities. The mechanical structure is rather unconventional, having been designed with the aim of minimizing any dead space in the assembly of the modules. Space resolution is ≈ ± 0.2 mm in the drift coordinate and ≈ ± 2mm in the delay coordinate.

Design and development of micro-strip stacked module prototypes to measure flying particle directions

Experience at high luminosity hadron collider experiments shows that tracking information enhances the trigger rejection capabilities while retaining high efficiency for interesting physics events. The design of a tracking based trigger for Super LHC (S-LHC), the already envisaged high luminosity upgrade of the LHC collider, is an extremely challenging task, and requires the identification of high-momentum particle tracks as a part of the Level 1 Trigger. Simulation studies show that this can be achieved by correlating hits on two closely spaced silicon strip sensors. This work focuses on the design and development of micro-strip stacked prototype modules and will also discuss the technical challenges in the construction and final detector performance. Studies of possible sensor spacing and wire-bonding techniques will be also presented. The prototypes have been built with the silicon sensors and electronics used to equip the present CMS Tracker. Correlation of signals collected from sensors are processed off detector. We will present the results of tests performed on the prototype modules in terms of the noise performance of the proposed stack geometry. Preliminary results in terms of signal over noise and tracking performance with cosmic rays will also be shown.

A device to characterize optical fibres

Abstract ATLAS is a general purpose experiment approved for the LHC collider at CERN. An important component of the detector is the central hadronic calorimeter; for its construction more than 600,000 Wave Length Shifting fibres (corresponding to a total length of 1120 km ) have been used. We have built and put into operation a dedicated instrument for the measurement of light yield and attenuation length over groups of 20 fibres at a time. The overall accuracy achieved in the measurement of light yield (attenuation length) is 1.5% (3%). We also report the results obtained using this method in the quality control of a large sample of fibres.

Tests of a scintillating-fibre tracking detector based on position-sensitive photomultiplier readout

Abstract We report the results of measurements performed using a tracking detector based on 835 μm scintillating fibres read out by two position-sensitive photomultipliers. A six-layer hodoscope consisting of 1.2 m long fibres has been built and tested using cosmic rays. Subsequently, two such hodoscopes have been assembled and tested using a hadron beam at the CERN PS. The efficiency per plane is found to be about 70% and the point resolution about 130 μm. The signal-to-noise ratio is about 2.4 and is dominated by crosstalk in the position-sensitive photomultipliers.

Design and development of micro-strip stacked module prototypes for tracking at S-LHC

Experience at high luminosity hadron collider experiments shows that tracking information enhances the trigger rejection capabilities while retaining high efficiency for interesting physics events [1]. The design of a tracking based trigger for Super LHC (S-LHC), the high luminosity upgrade of the LHC collider [2], is an extremely challenging task requiring the identification of high-momentum tracks as a part of the Level 1 trigger decision. Simulation studies show that this can be achieved by correlating hits on two closely spaced silicon strip sensors. This paper focuses on the design and development of micro-strip stacked prototype modules and their performance. The prototypes have been built with the silicon sensors and electronics used to equip the present CMS Tracker [3]. Correlation of signals collected from sensors are processed off detector. Preliminary results in terms of signal over noise and tracking performance with cosmic rays will be also shown.

Design and studies of micro-strip stacked module prototypes for tracking and trigger at the SLHC

Prototype silicon microstrip modules meant to generate Level 1 trigger information in future tracker implementations at super-high luminosity accelerators have been built using spare components from the current CMS Tracker and tested on a 120 GeV muon beam at the CERN SPS North Area. Tracking information from a silicon microstrip beam telescope has also been used in order to precisely reconstruct tracks and incidence angles. Data has been collected from prototypes with different geometries and interconnection schemes and at different angles of beam incidence, simulating the effect of a solenoidal magnetic field on particles of different transverse momentum p⊥.