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The performance of a readout system for the Synchrotron Radiation Detector (SRD) is studied. The detector is proposed as part of the Alpha Magnetic Spectrometer experiment, an experiment to fly on the International Space Station (ISS) beginning of 2005. The SRD is designed to detect the synchrotron radiation from electrons and positrons (TeV energy range) produced in the earth''s magnetic field. For the planned array of scintillators and photomultipliers a readout system is chosen, which is compact, space qualified and has a low-power consumption. The low-power chip APV, originally designed for the CMS experiment at LHC (CERN), is foreseen for the readout. To overcome the diffuse background from photons and charged particles the SRD readout must have a time resolution better than 10 ns. The intrinsic time resolution (sigma from Gauss fit) of the APV25-S0 was found to be 0.46±0.01 and 0.68±0.02 ns for the APVM, whereas the time resolution of the photomultiplier-APV readout system was measured to be 2.73±0.10 ns for the APV25-S0 and 2.90±0.21 ns for the APVM. The investigated timing capabilities of the photomultiplier-APV readout system show that the APV chip is suitable for the SRD readout. [Copyright &y& Elsevier]

Abstract: Following the decision to maintain the International Space Station (ISS) on orbit until at least 2020 (possibly until 2028) the AMS collaboration decided to correspondingly extend the lifetime of the experiment. Since the limited amount of helium used to cool the superconducting magnet allowed for only a limited run time of the experiment, a change from the superconducting magnet to the permanent magnet used in AMS-01 became necessary. Due to the lower magnetic field, to maintain the resolution the silicon tracker also had to be reconfigured with the installation of a silicon plane on the top of the experiment and a new plane above the electromagnetic calorimeter. [Copyright &y& Elsevier]

Abstract: The Alpha Magnetic Spectrometer is designed for a long duration measurement of the cosmic-ray spectra at an altitude of 400km. The particle rigidity and specific energy loss are measured by a silicon tracker located in a 0.8T field. Ground results for the position resolution, detection efficiency and charge determination for singly and doubly charged relativistic particles are presented and discussed in the context of the spaceborne detector. [Copyright &y& Elsevier]

Abstract: The silicon tracker of the AMS-02 detector measures the trajectory in three dimensions of electrons, protons and nuclei to high precision in a dipole magnetic field and thus measures their rigidity (momentum over charge) and the sign of their charge. In addition, it measures the specific energy loss of charged particles to determine the charge magnitude. Ladders from the AMS-02 tracker have been exposed to ion beams at CERN and GSI to study their response to nuclei from helium up to the iron group. The longest ladder, , verified in the tests contains 12 sensors. Good charge resolution is observed up to iron. [Copyright &y& Elsevier]

The Alpha Magnetic Spectrometer (AMS-02) is an experiment which will be mounted on the international space station (ISS) to measure primary cosmic ray spectra in space. A key element is the transition radiation detector (TRD) to extract an e+ or p- signal reducing the p+ or e- background by a rejection factor 102-103 in an energy range from 10 to 300 GeV. This will be used in combination with an electromagnetic calorimeter to provide overall p+ rejection of 106 at 90% e+ efficiency. The detector consists of 20 layers of 6 mm diameter straw tubes alternating with 20 mm layers of polyethylene/polypropylene fleece radiator. The tubes are filled with a 4:1 mixture of Xe:CO2 at 1 bar absolute pressure from a recirculating gas system designed to operate >3 years in space. There are in total 5248 straw tubes which are read out by a custom-made DAQ system in less than 80 μs. The electronics must be low in power consumption and sustain the stringent requirements of operation in space. The construction of the detector and its electronics is presented in this paper. [ABSTRACT FROM AUTHOR]

The Prototype Synchrotron Radiation Detector (PSRD) is a small-scale experiment designed to measure the rate of low-energy charged particles and photons in near the Earth''s orbit. It is a precursor to the Synchrotron Radiation Detector (SRD), a proposed addition to the upgraded version of the Alpha Magnetic Spectrometer (AMS-02).The SRD will use the Earth''s magnetic field to identify the charge sign of electrons and positrons with energies above 1 TeV by detecting the synchrotron radiation they emit in this field. The differential energy spectrum of these particles is astrophysically interesting and not well covered by the remaining components of AMS-02. Precise measurements of this spectrum offer the possibility to gain information on the acceleration mechanism and characteristics of all cosmic rays in our galactic neighbourhood. The SRD will discriminate against protons as they radiate only weakly.Both the number and energy of the synchrotron photons that the SRD needs to detect are small. The identification is complicated by the presence of a large particle and photon background. Existing measurements of these backgrounds are insufficient for the construction of the large-scale SRD, so a measurement in space was indispensable.The PSRD was designed to fly as a Space Shuttle secondary payload, within the Shuttle Small Payloads Project. The flight on board the Space Shuttle Endeavour took place from 5 to 17 December 2001.The scientific goal, hardware and the flight of the PSRD are described in this report. [Copyright &y& Elsevier]

The components of the PSRD, a detector to study the flux of X-rays and charged particles in the keV–MeV energy range in outer space, are described. The device is a precursor for the Synchrotron Radiation Detector, which is one of the detector components of the Alpha Magnetic Spectrometer (AMS02). The AMS02 will be operated for several years on the International Space Station. [Copyright &y& Elsevier]