The Cosmic Ray Energetics And Mass (CREAM) instrument is configured with a suite of particle detectors to measure TeV cosmic-ray elemental spectra from protons to iron nuclei over a wide energy ...range. The goal is to extend direct measurements of cosmic-ray composition to the highest energies practical, and thereby have enough overlap with ground based indirect measurements to answer questions on cosmic-ray origin, acceleration and propagation. The balloon-borne CREAM was flown successfully for about 161days in six flights over Antarctica to measure elemental spectra of Z=1–26 nuclei over the energy range 1010 to >1014eV. Transforming the balloon instrument into ISS-CREAM involves identification and replacement of components that would be at risk in the International Space Station (ISS) environment, in addition to assessing safety and mission assurance concerns. The transformation process includes rigorous testing of components to reduce risks and increase survivability on the launch vehicle and operations on the ISS without negatively impacting the heritage of the successful CREAM design. The project status, including results from the ongoing analysis of existing data and, particularly, plans to increase the exposure factor by another order of magnitude utilizing the International Space Station are presented.
In-beam aerogel light yield characterization for the AMS RICH detector Aguilar-Benitez, M.; Arruda, L.; Barao, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2010, Letnik:
614, Številka:
2
Journal Article
Recenzirano
The ring imaging Cherenkov (RICH) detector of the AMS-02 spectrometer provides a very precise measurement of the electric charge and velocity. The RICH detector is composed of a conical reflector ...ended on top by a dual radiator plane made of sodium fluoride and aerogel, and at the bottom by a detector plane made of pixelized photomultipliers. The vast majority of the events (
∼
90
%
) that are collected in the RICH cross the aerogel radiator. Therefore, the choice and characterization of the aerogel radiator is essential for reaching the design goals. A prototype of the RICH detector was built for both concept proof and testing of the different elements. Beam tests with the RICH prototype and using several aerogel radiator samples were performed at CERN in 2002 and 2003. This note summarizes the method used and the results obtained for the light yield of different aerogel samples.
Characterization study of silica aerogel for Cherenkov imaging Sallaz-Damaz, Y.; Derome, L.; Mangin-Brinet, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2010, Letnik:
614, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Different methods to measure the characteristics of silica aerogel tiles used as Cherenkov radiator in the CREAM and AMS experiments have been investigated to optimize the detector performances. The ...measurement accuracy dictated by the physics objectives on the velocity and charge resolutions set stringent requirements on the aerogel refractive index determination, namely
Δ
n
∼
1.5
×
10
−
4
and
Δ
n
∼
5
×
10
−
4
for the AMS and CREAM imagers, respectively. The matching of such accuracies for this material turned out to be a metrological challenge, and finally led to a full R&D program, to develop an appropriate characterization procedure. Preliminary studies performed with a standard refractive index measurement technique (laser beam deviation by a prism) have revealed a significant systematic index nonuniformity for the AMS tiles at a level
(
10
−
3
)
, not acceptable considering the aimed accuracy. These large variations were confirmed in a beam test. A second method, mapping the transverse index gradient by deflection of a laser beam entering normally to the tile has then been developed. It is shown that this procedure is suitable to reach the required accuracy, at the price of using both methods combined. The several hundreds of tiles of the radiator plane of the CREAM and AMS Cherenkov imagers were characterized using a simplified procedure, however, appropriate for each case, compromising between the amount of work and the time available. The experimental procedures and set-ups used are described in the text, and the obtained results are reported.
The high flux proton component observed by AMS below the geomagnetic cutoff can be well accounted for by assuming these particles to be secondaries originating from the interaction of cosmic ray ...protons with the atmosphere. Simulation results are reported.
A measurement of the cosmic ray positron fraction e+/(e++e−) in the energy range of 1–30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space ...Shuttle flight in June 1998. A proton background suppression on the order of 106 is reached by identifying converted bremsstrahlung photons emitted from positrons.
The RICH counter of the AMS experiment Buenerd, M.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
04/2003, Letnik:
502, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
The RICH counter of the AMS experiment is described and its expected performances discussed. Prototype results are reported.
Prototype study of the Cherenkov imager of the AMS experiment Aguayo, P.; Aguilar-Benitez, M.; Arruda, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2006, Letnik:
560, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The AMS experiment includes a Cherenkov imager for mass and charge identification of charged cosmic rays. A second generation prototype has been constructed and its performances evaluated both with ...cosmic ray particles and with beam ions. In-beam tests have been performed using secondary nuclei from the fragmentation of
20
GeV
/
c
per nucleon Pb ions and
158
GeV
/
c
per nucleon In from the CERN SPS in 2002 and 2003. Partial results are reported. The performances of the prototype for the velocity and the charge measurements have been studied over the range of ion charge
Z
≲
30
. A sample of candidate silica aerogel radiators for the flight model of the detector has been tested. The measured velocity resolution of the detector was found to scale with
Z
-
1
as expected, with a value
σ
(
β
)
/
β
≈
0.7
–
110
-
3
for singly charged particles and an asymptotic limit in
Z of 0.4–
0.6
×
10
-
4
. The measured charge resolution obtained for the
n
=
1.05
aerogel radiator material selected for the flight model of the detector is
σ
(
Z
)
=
0.18
(statistical)
⊕
0.015 (systematic), ensuring a good charge separation up to the iron element, for the prototype in the reported experimental conditions.
In-beam tests of the AMS RICH prototype with 20 A GeV/c secondary ions Baret, B.; Aguayo, P.; Benitez, M.A. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
06/2004, Letnik:
525
Conference Proceeding
A prototype of Proximity Focussing Ring Imaging Cherenkov counter has been built and tested with several radiator materials and configurations, including a dual radiator configuration, using ...separately cosmic-ray particles and 12C beam fragmentation products at several energies. Counter prototype and experimental setup are described, and the results of measurements are reported and compared with simulation results. The performances are discussed in the perspective of the final counter design.
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