Silicon calorimeter for cosmic antimatter search

Abstract The silicon sampling calorimeter presented is conceived as a fine grained imaging device to carry out studies of the anti-matter component in the primary cosmic radiation; it will be used in balloon payload program starting in 1993. The first sampling layer (48×48 cm2) of this silicon calorimeter has been completed and successfully tested. We report the first results form studies performed at the CERN PS t7 beam. The complete calorimeter contains 20 xy sampling layers (strip pitch 3.6 mm) interleaved with 19 showering material planes (tungsten 0.5 X0). This allows to picture the transverse distributions of the shower in both coordinates at each sampling. The outstanding imaging capabilities reflects in high particle identification power. Preliminary results from beam tests performed with antiprotons at 3.5 GeV on a tower prototype of the calorimeter are reported

A silicon imaging calorimeter prototype for antimatter search in space: experimental results

Abstract This report presents the results obtained with a prototype silicon-tungsten (Si-W) electromagnetic calorimeter, conceived as a fine-grained imaging device to carry out studies of the antimatter component in primary cosmic radiation. The calorimeter prototype contains 20 x , y sampling layers interleaved with 19 showering material planes. One sensitive layer is obtained with two silicon strip detectors (Si-D) (60 × 60) mm 2 , each divided into 16 strips, 3.6 mm wide; the two detectors are assembled back to back with perpendicular strips. This allows the transverse distributions of the shower in both coordinates at each sampling (0.5 X 0 ) to be pictured. The basic characteristics of the design and the experimental results obtained on a test beam at the CERN proton synchrotron (PS) for electrons and pions are reported. The main results presented are the response of the calorimeter to the electron at various energies (1–7 GeV), and the transverse shower profiles at different calorimeter depths as well as the patterns of the electromagnetic shower and those of the interacting and non-interacting pions. The capability of the calorimeter in measuring the direction of the incoming electromagnetic particle from the pattern of the shower has been evaluated at different energies. These results are encouraging in view of the possible use of this detector to search for high-energy γ sources in space

The COMPASS Experiment at CERN

The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.Comment: 84 papes, 74 figure

A study for a satellite system to locate gamma-ray bursters

SIGLEITItal

An optical recording system based on a fast CCD sensor for biological imaging

This paper presents technical details, hardware and software of a complete imaging system which uses a fast CCD sensor and a 41 Msample/s A/D converter to acquire full-frame 12 bit/pixel digitized images with a time resolution of 1.25 ms/image. This apparatus permits to resolve intracellular Ca2+ gradients in individual cells as well as the spatio-temporal pattern of neural activity of cell assemblies in neural tissue

Intracellular Gradients of Free Calcium Visualized in Sensory and Neuronal Cells By a High-Performance Fluorescence Imaging System

This paper describes results obtained with a novel imaging system based on a fast CCD device. Sensor's output was digitized at 12 bit/pixel by customized electronics, reaching acquisition rates as high as 800 frames/s with a full-frame resolution of 128128 pixels. The software developed for the project permitted the sequential capture of thousands of images directly to host PC RAM without frame loss even at the maximum readout rate (16 MHz). It is shown that the high spatio-temporal resolution of this apparatus is of value when investigating the time-course of rapid intracellular Ca2 fluorescence transients, particularly those associated with neuronal action potentials near physiological temperature

Monte Carlo studies of the COMPASS RICH 1 optical properties

Baum G, Birsa R, Bradamante F, et al. Monte Carlo studies of the COMPASS RICH 1 optical properties. In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. Nucl.Instrum.Meth. A. Vol 433. ELSEVIER SCIENCE BV; 1999: 401-405.A dedicated Monte Carlo has been built to study the optical properties of the RICH 1 detector presently under construction for the COMPASS experiment at CERN. In this paper we focus on the optimization of the position of the photon detector with respect to the RICH mirror and on the alignment of the mirror elements forming the mirror surface. (C) 1999 Elsevier Science B.V. All rights reserved

The COMPASS RICH1 detector

Baum G, Birsa R, Bradamante F, et al. The COMPASS RICH1 detector. In: Nuclear Physics B - Proceedings Supplements. Nucl.Phys.Proc.Suppl. Vol 78. ELSEVIER SCIENCE BV; 1999: 354-359.A large acceptance gas RICH detector is presently under construction for the spectrometer of the COMPASS Experiment. Tts design parameters are presented and the main characteristics of the vessel, the mirrors system, the photon detectors and the front-end electronics are-discussed together with some results from prototyping activities