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[en] The CHARM II Collaboration has built a massive, fine-grained calorimeter for the study of the elastic scattering νμ(-)e → νμ(-)e. A short description of the detector will be followed by the presentation of some results obtained by exposing 40 of the 441 planes of the calorimeter to a beam of electrons and pions. Comments will be given about the conditioning procedure followed for the 154560 limited streamer tubes which compose the active part of the calorimeter. (orig.)
[en] Recently, we have developed high precision carbon-interspaced antiscatter grids to be suitable for digital radiography (DR) adopting a precise sawing process. For systematic evaluation of the grid performance, we prepared several sample grids having different grid frequencies (4.0-8.5 lines/mm) and grid ratios (5:1-10:1) and established a well-controlled test condition based upon the IEC standard. In this paper, we presented the performance characteristics of the carbon-interspaced grids in terms of the transmission of primary radiation (Tp), the transmission of scattered radiation (Ts), the transmission of total radiation (Tt), contrast improvement factor (Cif), and Bucky factor (B). We also described the grid line artifact, known as a moire pattern, which may be the most critical problem to be solved for the successful grid use in DR. We examined the factors that affect the moire pattern by integrating the sample grids with an a-Se based flat panel detector having a 139 μmx139 μm pixel size.
[en] The size and complexity of the CMS detector makes the Data Quality Monitoring (DQM) system very challenging. Given the high granularity of the CMS sub-detectors, several approaches and tools have been developed to monitor the detector performance closely. We describe here the History DQM, a tool allowing the detector performance monitoring over time.
[en] A combined Bragg-PPAC ionization detector has been developed for registration and identification of light charged particles from photonuclear reactions at tagged photon beams. The detector is described and also its performance, which was obtained in a test experiment at the tagged photon beam
[en] We have designed and developed the flight model silicon micro-strip detector (FM-SSD) for Large Area Space Telescope (GLAST). The concepts and details of the sensor design are described and the results of production testing of the SSDs are reported. A total of 11,500 FM-SSDs were produced in the 2-year time span from the start of 2001 to the end of 2003. The fabrication was done on the 6-in process line at Hamamatsu Photonics Company. The properties of each SSD were determined by measuring a set of specific parameters. The leakage current and dead channel rate establish a new performance standard for SSD mass production, indicating that the SSD design and fabrication technologies have been well optimized and are well matured
[en] The global as well as intrinsic alignment of any spectrometer impacts directly on its performance and the quality of the achievable physics results. An overview of the current alignment procedure of the DiElectron Spectrometer HADES is presented with an emphasis on its main features and its accuracy. The sequence of all steps and procedures is given, including details on photogrammetric and track-based alignment
[en] There is today widespread use of plastic scintillating fibers in particle physics, mainly for calorimetric and tracking applications. In the case of calorimeters, we have to cope with very massive detectors and a large quantity of scintillating fibers. The CHORUS Collaboration has built a new detector to search for νμ-ντ oscillations in the CERN neutrino beam. A crucial task of the detector is ruled by the high-energy resolution calorimeter. For its construction more than 400 000 scintillating plastic fibers have been used. In this paper we report on the design and performance of a new instrument for the high-statistics measurement of the fiber properties, in terms of light yield and light attenuation length. The instrument has been successfully used to test about 3% of the total number of fibers before the construction of the calorimeter. ((orig.))
[en] As a result of a research and development activity on monolithic low noise structures based on the DMILL process, some basic design criteria have been drawn. These criteria are presented in this paper to show how they can lead to preamplifiers of outstanding noise characteristics that suit applications ranging from calorimetry to tracking and radiation spectrometry. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)
[en] The proximity focused hybrid photo diode (HPD), a new type of light detector insensitive to uniform magnetic fields, will be employed in the inner region of the FINUDA detector coupled to a simple, cheap, low noise and low input impedance fast preamplifier (PA): the design and the performances are presented and discussed. (author)