Characterization method to achieve simultaneous absolute PDE measurements of all pixels of an ASTRI Mini-Array camera tile

Autor(es)

Bonanno, G. ; Romeo, G. ; Occhipinti, G. ; Timpanaro, M. C. ; Grillo, A.

• Tipo de documento: Artigo Científico
• Fonte: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SP; v. 980, p. 7-pg., 2020-11-11.

Resumo

Recently, the Istituto Nazionale di Astrofisica (INAF) has placed a contract with Hamamatsu Photonics to acquire hundreds of Silicon Photomultipliers (SiPM) files to build 10 cameras with 37 files each for the ASTRI Mini-Array (MA) project. Each file is made up of 8 x 8 pixels of 7 x 7 mm(2) with micro-cells of 75 mu m. To check the quality of the delivered files a complex and accurate test plan has been studied. The possibility to simultaneously analyse as many pixels as possible becomes of crucial importance. Dark Count Rate (DCR) versus over-voltage and versus temperature and Optical Cross Talk (OCT) versus over-voltage can be easily measured simultaneously for all pixels because they are carried out in dark conditions. On the contrary, simultaneous Photon Detection Efficiency (PDE) measurement of all pixels of a file is not easily achievable and needs an appropriate optical set-up. Simultaneous measurements have the advantage of speeding up the entire procedure and enabling quick PDE comparison of all the file pixels. The paper describes the preliminary steps to guarantee an accurate absolute PDE measurement and the investigation the capability of the electronics to obtain simultaneous PDE measurements. It also demonstrates the possibility of using a calibrated SiPM as reference detector instead of a calibrated photodiode. The method to achieve accurate absolute PDE of four central pixels of a file is also described. (AU)

• Processo FAPESP: 13/10559-5 - Investigação de fenômenos de altas energias e plasmas astrofísicos: teoria, simulações numéricas, observações e desenvolvimento de instrumentação para o Cherenkov Telescope Array (CTA)
• Beneficiário: Elisabete Maria de Gouveia Dal Pino
• Modalidade de apoio: Auxílio à Pesquisa - Projetos Especiais