Study of linearity of LYSO crystal for the high energy cosmic radiation detection (HERD) facility

Abstract

The high energy cosmic-radiation detection (HERD) facility is a space mission designed for detecting cosmic ray (CR) electrons, γ -rays up to tens of TeV and CR nuclei from proton to iron up to several PeV. The main instrument of HERD is a 3-D imaging calorimeter (CALO) composed of nearly ten thousand lutetium yttrium orthosilicate (LYSO, with cerium doping) crystal cubes. A large dynamic range of single HERD CALO Cell (HCC) is necessary to achieve HERD's PeV observation objectives, which means that the response of HCC should maintain a good linearity from minimum ionizing particle (MIP) calibration to PeV shower maximum. In order to study the linearity of HCC over such a large energy range, a beam test has been implemented at the E2 and E3 beam lines of BEPC. High intensity pulsed electron beam provided by E2 line is used for producing high energy density within HCC; π + /proton provided by E3 line are used for HCC calibration. The results show that no saturation effect occurs and the linearity of HCC is better than 10% from 30 MeV (1 MIP) to 1.1 × 10 3 TeV (energy density is 93 TeV/cm 3 ), which can meet the requirement mentioned above.

Introduction to the High Energy cosmic-Radiation Detection (HERD) Facility onboard China’s Future Space Station

“…image intensified CMOS (IsCMOS) is proposed, which can greatly reduce the complexity of onboard electronics. Linearity of light output of LYSO crystal in the range from 30 MeV to 1 PeV was verified at BEPC E2 by using calibrated electron bundles [29]. So the key technology of HERD is the realization of dynamic range of 10 7 in the IsCMOS system.…”

A novel 3-D calorimeter for the High Energy cosmic-Radiation Detection (HERD) Facility onboard China’s Future Space Station

“…Each LYSO crystal, with dimensions of 3cm*3cm*3cm, has a radiation length of 1.14 cm. Linearity of light output of LYSO crystal in the range from 30 MeV to 1 PeV was demonstrated at BEPC E2 by using calibrated electron bundles [12]. A novel method of reading out the LYSO signals by Wavelength Shifting Fiber (WLSF) and image intensified CMOS (ISCMOS) is applied, which can greatly reduce the complexity of onboard electronics.…”

Study on the Optimized Energy Resolution of Scintillator Detectors Based on SiPMs and LYSO:Ce

“…The scintillation detector is typically composed of a photosensitive detector, a scintillator and back-end electronic devices, which has been widely used in particle physics experiments [1], biomedical research (e.g., positron emission tomography, PET [2]), space exploration [3] and gamma spectroscopy [4], etc. Among all these scintillation materials used for the scintillation detector, LYSO is found to feature high density, high light output, fast decay time and non-hygroscopic, showing great potential to improve the performance of scintillation detectors [5].…”