[show abstract][hide abstract] ABSTRACT: 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.
Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment 01/2010; · 1.14 Impact Factor
[show abstract][hide abstract] ABSTRACT: The Alpha Magnetic Spectrometer (AMS), whose final version AMS-02 is to be installed on the International Space Station (ISS) for at least 3 years, is a detector designed to measure charged cosmic ray spectra with energies up to the TeV region and with high energy photon detection capability up to a few hundred GeV. It is equipped with several subsystems, one of which is a proximity focusing RICH detector with a dual radiator (aerogel+NaF) that provides reliable measurements for particle velocity and charge. The assembly and testing of the AMS RICH is currently being finished and the full AMS detector is expected to be ready by the end of 2008. The RICH detector of AMS-02 is presented. Physics prospects are briefly discussed.
[show abstract][hide abstract] ABSTRACT: The AMS detector, to be installed on the International Space Station, includes a Ring Imaging Cerenkov detector with two different radiators, silica aerogel (n=1.05) and sodium fluoride (n=1.334). This detector is designed to provide very precise measurements of velocity and electric charge in a wide range of cosmic nuclei energies and atomic numbers. The detector geometry, in particular the presence of a reflector for acceptance purposes, leads to complex Cerenkov patterns detected in a pixelized photomultiplier matrix. The results of different reconstruction methods applied to test beam data as well as to simulated samples are presented. To ensure nominal performances throughout the flight, several detector parameters have to be carefully monitored. The algorithms developed to fulfill these requirements are presented. The velocity and charge measurements provided by the RICH detector endow the AMS spectrometer with precise particle identification capabilities in a wide energy range. The expected performances on light isotope separation are discussed.