Charge Resolution Study on AMS-02 Silicon Layer-0 Prototype

Abstract

The work presented in this paper represents a preliminary study on the performance of the new Silicon tracker layer, Layer 0 (L0), that will be installed on top of the Alpha Magnetic Spectrometer (AMS-02), at the end of 2024. AMS-02 is a cosmic ray (CR) detector that has been operating on the International Space Station (ISS) since May 2011. Thanks to its nine-layer Silicon tracker, this apparatus can perform high-energy CR measurements with an unprecedented level of statistics and precision. However, high-Z (Z ≥ 15) CR nuclei statistics is strongly affected by fragmentation along the detector: with the installation of the new Silicon layer, it will be possible to achieve new unique high-energy (TeV region) measurements of those nuclei along with increased statistics for all nuclei up to Zinc. To achieve this, a Silicon ladder prototype, which will be part of the final Silicon layer, was exposed to an ion test beam at the super-proton synchrotron (SPS) of CERN to characterize its charge resolution and the readout electronics. Preliminary results have shown a charge resolution of 10 % for nuclei up to Z = 7.

Keywords

• AMS-02 Layer 0 upgrade
• silicon micro-strip detector
• nuclei
• charge resolution
• ADC
• cosmic ray