The AMS-02 TRD for the international space station Hauler, F.; Bartoloni, A.; Becker, U. ...
IEEE transactions on nuclear science,
2004-Aug., 2004-08-00, 20040801, Letnik:
51, Številka:
4
Journal Article
Recenzirano
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/sup +/ or p/sup -/ signal reducing the p/sup +/ or e/sup -/ background by a rejection factor 10/sup 2/--10/sup 3/ in an energy range from 10 to 300 GeV. This will be used in combination with an electromagnetic calorimeter to provide overall p/sup +/ rejection of 10/sup 6/ at 90% e/sup +/ 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:CO/sub 2/ 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 /spl mu/s. 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.
This study describes the successful upgrade of a mechanically pumped CO2 two-phase cooling system in space by designing a new pump module for the Alpha Magnetic Spectrometer-02 on the International ...Space Station. Key factors for mission success are emphasized, including achieving high coolant filling accuracy within 10% of the target and maintaining system stability within ±1 °C. The impact of adding radiators to improve cooling efficiency is examined, and it is found that operating multi-radiators out-of-phase does not significantly affect system reliability. The centrifugal pump design is shown to allow for better lubricant circulation, while the in-house designed controller incorporates protective measures to prevent cavitation, overheating, and over-current. This research advances the understanding of circulation loop systems and their upgrades in space and demonstrates the potential for extending the lifetime of space-borne mechanically pumped two-phase cooling systems.
•First in-space upgrade of a pumped two-phase cooling system.•Quantitative on-orbit fluid transfer achieves 7% accuracy.•Superior system control stability of 1 °C with multiple out-f-phase radiators.•Prolonged mechanical pump lifetime via hardware and software manners.
Construction and test of MDT chambers for the ATLAS muon spectrometer Bauer, F.; Bratzler, U.; Dietl, H. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2001, Letnik:
461, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The Monitored Drift Tube (MDT) chambers for the muon spectrometer of the ATLAS detector at the Large Hadron Collider (LHC) consist of 3–4 layers of pressurized drift tubes on either side of a space ...frame carrying an optical monitoring system to correct deformations. The full-scale prototype of a large MDT chamber has been constructed with methods suitable for large-scale production. X-ray measurements at CERN showed a positioning accuracy of the sense wires in the chamber of better than the required 20
μm (rms). The performance of the chamber was studied in a muon beam at CERN. Chamber production for ATLAS now has started.
The Transition Radiation Detector of the AMS-02 experiment on the International Space Station is used for the separation of cosmic-ray positrons and electrons from protons and anti-protons, and for ...the identification of nuclei up to carbon (Z≤6). We present the Geant4 simulation that is used to describe the ionization and transition radiation processes and compare its results to flight data from AMS-02. After applying empirical corrections to the simulated data, the particle energy deposition and likelihood distributions in the TRD are described with high accuracy.
A test of the laser alignment system ALMY at the TTF-FEL Roth, S; Schael, S; Schmidt, G
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2001, Letnik:
475, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The laser alignment system ALMY was tested at the
15
m
long undulator section of the TESLA test facility. The positions of the undulator modules relative to each other have been determined with a ...precision of
0.1
mm
, limited by the accuracy of the mechanical support of the sensors. Additionally, ALMY allows one to measure movements or drifts over several days and we found that the undulator components are stable within
10
μm
. The resolution of the sensors is better than
2
μm
over a distance of
15
m
.
Status of AMS-TRD-Straw modules Kirn, Th; Chung, C.H.; Dömmecke, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2004, Letnik:
522, Številka:
1
Journal Article
Recenzirano
The AMS02 experiment will be installed on the International Space Station for a data taking period of 3 years. The TRD consists of 20 layers of straw modules and fleece radiator with a total of 328 ...modules (16 straws each). The housing consists of a conically shaped octagon structure made out of CFC-Al-honeycomb material and is closed by a lower and upper honeycomb plate. The gas is a 80:20 Xe/CO
2 mixture. The straw modules will be operated in proportional mode at a gasgain of 3000. The signals are readout by VA chips. The detector is under construction at RWTH Aachen, the gas system will be built at MIT, slow-control at INFN Rome and DAQ at TH Karlsruhe. In the presentation special emphasis will be dedicated to the space qualification aspects and the status of the straw module production.
Novel semi-transparent optical position sensors (‘ALMY sensors’) have been developed for the alignment monitoring systems of modern large-area tracking detectors. More than 10 sensors can be aligned ...along one laser beam. The thin-film amorphous silicon strip sensors provide up to 90% transmittance for red laser light combined with minimum beam distortion and a typical position resolution of 1
μm over a sensitive area of several square centimeters.
The monitored drift tube (MDT) chambers for the muon spectrometer of the ATLAS detector at the Large Hadron Collider (LHC) consist of three or four layers of pressurised drift tubes on either side of ...a space frame carrying an optical deformation monitoring system. The chambers have to provide a track position resolution of 40 /spl mu/m with a single-tube resolution of at least 80 /spl mu/m and a sense wire positioning accuracy of 20 /spl mu/m (rms). The feasibility was demonstrated with the full-scale prototype of one of the largest MDT chambers with 432 drift tubes of 3.8 m length. For the ATLAS muon spectrometer, 88 chambers of this type have to be built. The first chamber has been completed with a wire positioning accuracy of 14 /spl mu/m (rms).
The CMS all-silicon tracker will cover a total area of
210
m
2
with 15
232 detector modules. It will be by far the largest silicon strip detector ever built. It consists of 10 barrel layers and 2×9 ...end cap layers inside a volume of about
5.6
m
length and
2.4
m
radius. One of the biggest challenges in constructing and building the CMS silicon strip detector is its operation temperature at −20°C. This article will focus on the mechanical structure and on the tracker alignment system.
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