Search results for " Detectors"
showing 10 items of 2027 documents
Beam study of irradiated ATLAS-SCT prototypes
2002
Abstract Prototypes of ATLAS-SCT modules with ABCD readout chips were tested in a 4 GeV/c pion beam at KEK's proton synchrotron. Of both SCT module geometries—barrel and forward—three identical modules were placed in the beam. One module of each type had been irradiated to 3×1014 protons/cm2 in the CERN PS previous to the beam test. A method has been developed to reconstruct the time-resolved shaper pulse from the binary hit information, allowing a more detailed study of the timing properties of the ABCD. The present results will be compared to a simulation of the charge collection and Front End electronics response.
Charge collection efficiency and resolution of an irradiated double-sided silicon microstrip detector operated at cryogenic temperatures
1999
Abstract This paper presents results on the measurement of the cluster shapes, resolution and charge collection efficiency of a double-sided silicon microstrip detector after irradiation with 24 GeV protons to a fluence of 3.5×10 14 p/cm 2 and operated at cryogenic temperatures. An empirical model is presented which describes the expected cluster shapes as a function of depletion depth, and is shown to agree with the data. It is observed that the clusters on the p-side broaden if the detector is under-depleted, leading to a degradation of resolution and efficiency. The model is used to make predictions for detector types envisaged for the LHC experiments. The results also show that at cryo…
Performance Studies of Pixel Hybrid Photon Detectors for the LHCb RICH Counters
2006
The Pixel Hybrid Photon Detector is a vacuum tube with a multi-alkali photo cathode, high voltage cross-focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a readout CMOS electronic chip fully encapsulated in the device. The Pixel HPD fulfils the requirements of the Ring Imaging Cherenkov counters of the LHCb experiment at LHC. The performances of the Pixel HPD will be discussed with reference to laboratory measurements, Cherenkov light imaging in recent beam tests, image distortions due to a magnetic field.
Characterisation and compensation of magnetic distortions for the pixel Hybrid Photon Detectors of the LHCb RICH
2005
Abstract The LHCb experiment at LHC, optimised for the study of CP violation, has two RICH detectors to provide particle identification in the momentum range ∼ 2 – 100 GeV / c . The stringent requirements on the photon detectors are met by the custom-made pixel Hybrid Photon Detector. The photon detectors need to operate in the fringe field of the LHCb dipole magnet which will produce distortions of the image detected on the pixel chip which is encapsulated inside the HPD. This paper reports on the experimental characterisation of the image distortions caused by an external magnetic flux density. These measurements allow for the development of a parameterisation of the effects and a compens…
Silicon detectors for forward tracking in ATLAS
1996
Abstract A 12 cm long silicon microstrip detector module with a fan geometry has been designed and constructed. The performance of the detector has been studied in a test beam at CERN. Results are presented on the hit efficiency and the position resolution as a function of position along the strips. With a hit efficiency of 99.5% and a spatial resolution of typically 35 μm the performance of these detectors exceeds that of other candidate technologies for the precision forward tracker of the ATLAS inner detector.
Silicon microstrip detectors for the ATLAS SCT
2002
Abstract The ATLAS Semiconductor Tracker at the Large Hadron Collider (LHC) will incorporate ∼20,000 individual silicon microstrip sensors representing ∼60 m 2 of silicon. Production and delivery of the sensors is already underway and scheduled for completion by late 2002. The sensors have been optimised for operation in the harsh radiation environment of the LHC, and subjected to an extensive qualification program in which their pre- and post-irradiation characteristics have been evaluated. The sensor design features are reviewed, together with their electrical characteristics and the Quality Control procedures adopted by ATLAS during production.
The Endcap Disc DIRC detector of PANDA
2019
Abstract At the international FAIR laboratory, an upcoming significant enlargement of the GSI installations near Darmstadt, Germany, the PANDA antiproton experiment will investigate fundamental questions of hadron physics in the charm quark energy range. Antiprotons in the 1.5 to15 GeV/c momentum range will interact with gas jet or pellet fixed targets. The Endcap Disc DIRC (Detection of Internally Reflected Cherenkov light) covers the forward endcap solid angle of the PANDA target spectrometer to positively identify charged kaons. Monte-Carlo simulations indicate that from 1 up to 4 GeV/c one can achieve kaon–pion separation with a separation power of at least 3 standard deviations. For th…
A $B_4C$-silicon target for the detection of neutrino interactions
1998
This note describes the construction of a target for neutrino interactions composed of passive boron carbide plates interleaved with silicon microstrip detectors. The target contains four layers of passive material with a total mass of 45 kg and 600 single--sided silicon microstrip detectors with a total surface of 1.14 m$^2$ distributed over five layers. It is installed in the NOMAD spectrometer at the CERN SPS neutrino beam. During the 1997 run about 8000 \nm\ charged current interactions were estimated to have occurred in the target. For these events it will be possible to perform a precise measurement of both vertex and kinematical variables. This will provide invaluable experience towa…
Radiation damage of heavy crystalline detector materials by 24GeV protons
2013
Abstract Samples of three heavy crystalline materials: PbWO4, Bi4Si3O12, and PbF2 were irradiated in a high-intensity 24 GeV proton beam at the CERN PS to fluencies of 3.8×1013 protons/cm2. The optical transmission radiation damage was measured and all crystals show a shift of the cutoff in the transmission spectrum that is not observed when the crystals are irradiated with γ radiation. This shift of the cutoff under proton irradiation seems to be a general property of the heavy crystalline materials. A mechanism for this proton-induced transmission damage is discussed.
Inclusive muon capture in light nuclei
1998
We study total muon capture rates in light nuclei, taking into account renormalizations of the nuclear vector and axial vector strengths. We estimate the influence in the results of uncertainties of the spin-isospin interaction parameter and nuclear densities. A few of these reactions are theoretical benchmarks for physics involving searches for neutrino oscillations. New experiments in muon capture in several targets are suggested, in the light of some discrepancies with theory, crudeness of some experimental results and relevance to neutrino physics.