D. Colonna

The CMS RPC gas gain monitoring system: An Overview and preliminary results

The status of the Compact Solenoid Spectrometer (CMS) Resistive Plate Counter (RPC) Gas Gain Monitoring (GGM) system developed at the Frascati Laboratory of INFN (Istituto Nazionale di Fisica Nucleare) is reported. The GGM system is a cosmic ray telescope based on small RPC detectors operated with the same gas mixture used by the CMS RPC system. The GGM gain and efficiency are continuously monitored on-line, thus providing a fast and accurate determination of any shift in working point conditions. The construction details and the first result of GGM commissioning are described.

An RPC-based Technical Trigger for the CMS Experiment

In the CMS experiment, sub-detectors may send special trigger signals, called “Technical Triggers”, for purposes like test and calibration. The Resistive Plate Chambers are part of the Muon Trigger System of the experiment, but might also produce a cosmic muon trigger to be used during the commissioning of the detectors, the CMS Magnet Test-Cosmic Challenge and the later running of CMS. The proposed implementation is based on the development of a new board, the RPC Balcony Collector (RBC); the test results on prototypes and their performance during the recent CMS Cosmic Challenge are presented.

Fiber optic sensors for space missions

Fiber optic sensors offer several advantages over conventional ones such as the immunity from electromagnetic interferences and the possibility of multiplexing many of them along the same fiber. Such sensors can be used to monitor local deformations on or inside the structures. In the paper will be mentioned techniques that can be used for embedding those sensors into several types of materials and possible applications in the field of Structural Health Monitoring (SHM). However the main objective is to show applications is in the field of scientific space experiments where precise position monitoring of particle detectors or of optical instrument can be crucial for the success of the mission. A real time position monitoring system based on fiber optic sensors is presented. The experimental results are compared with a conventional optical technique.

A novel approach for an integrated straw tube-microstrip detector

We report on a novel concept of silicon microstrips and straw tubes detector, where integration is accomplished by a straw module with straws not subjected to mechanical tension in a Rohacell/spl reg/ lattice and carbon fiber reinforced plastic shell. Results on mechanical and test beam performances are reported as well.

MICROMETRIC POSITION MONITORING USING FIBER BRAGG GRATING SENSORS IN SILICON DETECTORS

We show R&D results including long term stability, resolution, radiation hardness and characterization of Fiber Grating sensors used to monitor structure deformation, repositioning and surveying of silicon detector in High Energy Physics.

TWO- AND THREE-DIMENSIONAL RECONSTRUCTION AND ANALYSIS OF THE STRAW TUBES TOMOGRAPHY IN THE BTEV EXPERIMENT

A check of the eccentricity of the aluminised kapton straw tubes used in the BTeV experiment is accomplished using X-ray tomography of the section of tubes modules. 2 and 3-dimensional images of the single tubes and of the modules are reconstructed and analysed. Preliminary results show that a precision better than 40 � m can be reached on the measurement of the straw radii.

Smart supporting structures in space applications

In this paper, we present an application devoted to measure the dynamic response of a prototype of a support of a star tracker. Four different techniques have been used and compared with each other. Specifically Electronic Speckle Pattern Interferometry and Speckle Shearography have been used as full field modal appropriation techniques, impact hammer and accelerometer as a broad band conventional technique and finally broad band with impact hammer and FBG sensor as a newly proposed methodology. Modal parameters have been retrieved using all the four methodologies described above and compared. We have demonstrated that FBG sensors can be used to retrieve modal parameters useful as indicators of the state of health of a structural component. When embedded the FBG can be used actively also during the qualification process of the smart component as well as in service for shape monitoring. This latter purpose is important for precision pointing instruments such as the star tracker under investigation.

A new configuration for a straw tube microstrip detector

We report on a novel concept of silicon microstrips and straw tubes detector, where integration is accomplished by a straw module with straws not subjected to mechanical tension in a Rohacell/spl reg/ lattice and carbon fiber reinforced plastic shell.