The AMS-RICH velocity and charge reconstruction

TL;DR

This paper discusses the design, reconstruction algorithms, and expected performance of the AMS-RICH detector on the ISS, which measures cosmic ray velocity and charge with high precision using complex Cerenkov pattern analysis.

Contribution

It introduces novel reconstruction algorithms for complex Cerenkov patterns and evaluates their performance for particle identification in the AMS-RICH detector.

Findings

Effective reconstruction methods demonstrated on test beam and simulated data.

The detector achieves high precision in velocity and charge measurements.

Potential for improved light isotope separation in cosmic ray analysis.

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.