Determination of the Lorentz Angle in Microstrip Silicon Detectors with Cosmic Muons

The microstrip silicon tracker of the CMS experiment will operate in a 4 T magnetic field in the harsh radiation environment of the Large Hadron Collider. The drift motion of the charge carriers will be therefore affected by the Lorentz force due to the high magnetic field. Furthermore, radiation damage will change in time the properties of this drift. In this note a method to measure the Lorentz angle from reconstructed tracks is presented and results obtained on Magnet Test and Cosmic Challenge data are compared to the values expected from a model, developed by the authors, which takes into account all the relevant parameters during the tracker lifetime (e.g. temperature and depletion voltage of the detectors)

Signals and Power Distribution in the CMS Inner Tracker

\begin{abstract} This Note describes how the interconnection between the 3540 modules of the CMS Inner Tracker has been approached, focusing on the signal, high voltage and low voltage line distribution. The construction and tests of roughly a thousand interconnects called ``Mother Cables" is described. \end{abstract

Design and test of the Digital Opto Hybrid Module for the CMS Tracker Inner Barrel and Disks.

One of the most important tasks to be performed in the CMS Tracker detector is the communication between hundreds of silicon modules and the central Control System under the supervision of the Data Acquisition System. To manage such complexity, modules are grouped in a hierarchical structure. Each group is controlled by a Communication and Control Unit (CCU). Several CCU form a ring with a Front End Controller as master. The entire Tracker Inner Barrel and Disks detector contains roughly 100 such rings called Control Rings. A description is given here of the implemented ring architecture for the detector and of the solutions found to provide a reliable and easy way to interconnect these groups

A study of charge collection processes on polycrystalline diamond detectors

Abstract We performed a study of charge collection distance (CCD) on medium to high-quality prototypes of diamond sensors prepared by Chemical Vapor Deposition (CVD). We studied the Charge Collection Efficiency in these materials supposing that it is limited by the presence of a recombination level and a distribution of trap levels centered at 1.7 eV from the band-edge. We also supposed that the exposition to ionizing radiation can make the trap levels ineffective (pumping effect). We have shown that these assumptions are valid by correlating the CCD to the pumping efficiency. Moreover, we have shown that the pumping efficiency is bias-dependent. We have explained our experimental results assuming that trapped carriers generate an electric field inside the diamond bulk

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

The magnetic spectrometer of the PAMELA satellite experiment

In this paper, we describe in detail the design and the construction of the magnetic spectrometer of the PAMELA experiment, that will be launched during 2003 to do a precise measurement of the energy spectra of the antimatter components in cosmic rays. This paper will mainly focus on the detailed description of the tracking system and on the solutions adopted to deal with the technical challenges that are required to build a very precise detector to be used in the hostile space environment

A powerful tracking detector for cosmic rays: the magnetic spectrometer of the PAMELA satellite experiment

Abstract The WiZaxd-PAMELA detector will be ready within some months to be installed on board of the Russian satellite Resurs-DK1. The satellite will follow, for at least 3 years, a quasi polar orbit with an inclination of 70.4° with respect to the equatorial plane. The experiment will allow the measurement of the antiproton and positron spectra within a wide momentum range and the search for light anti-nuclei in cosmic rays. The detector subsystems have been tested and the final assembly phase is in progress. In this paper we describe the structure of the PAMELA magnetic spectrometer, its current status and some precautions taken to satisfy the requirements of the mission

The silicon microstrip detectors of the PAMELA experiment: simulation and test results

Abstract The PAMELA detector will fly at the beginning of 2004 on board the Russian satellite Resurs–DK for a 3-year mission designed to study mainly antiparticles in cosmic rays. The core of the apparatus is a magnetic spectrometer in which silicon microstrip detectors are employed. A dedicated simulation study, tuned on beam test data, is presented: it allows to determine the best position finding algorithm for different incidence angles

The PAMELA silicon tracker

Abstract The silicon tracker of the PAMELA apparatus has been assembled and it is ready to fly on-board the Russian satellite Resurs DK for a 3-year mission. The experiment will study, mainly, spectra of particles and antiparticles in cosmic rays. The magnetic spectrometer's primary goal is to precisely measure momenta of charged particles, whose trajectories have been bent by a permanent magnet. The detector is composed of 6 planes of double-sided silicon microstrip detectors, inserted between adjacent modules of a permanent magnet which produces an almost uniform magnetic field inside a rectangular cavity that particles cross. The spatial resolution of the detectors is about 3 μm for the bending coordinate. The development of such detectors required a complex manufacturing procedure in order to preserve the physical performance in a device suitable for a space mission. In the construction phase data originating from both beam tests and simulation helped to check the detector's characteristics and to optimize the achievable spatial resolution. The development and the final assembling of these detectors are described in this paper