Optimization of BaF2 positron-lifetime spectrometer geometry based on the Geant4 simulations

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:334

Article

Dubov, L. Yu.²  Grafutin, V. I.¹  Funtikov, Yu. V.¹  Shtotsky, Yu. V.²  Elnikova, L. V.¹ 

[1] FSBI RF SSC Inst Theoret & Expt Phys, Moscow 117218, Russia

[2] Natl Res Nucl Univ MEPhI, Moscow 115409, Russia

关键词: Positron annihilation lifetime spectroscopy;    Spectrometer geometry;    Geant4 simulation;   

DOI  :  10.1016/j.nimb.2014.05.006

来源: Elsevier

【 摘 要 】

Incorrect choice of measuring experimental geometry and energy windows for a positron-lifetime spectrometer with BaF2 scintillators can lead to a significant distortion in a measured spectrum. Contribution of the distorted events for a non-optimal geometry may exceed 50%. It reduces the measured lifetimes of the spectral components and redistributes their intensities. The Geant4 simulation allows to estimate an influence of the measuring geometry on the spectrum distortion and to choose the most appropriate energy windows. The optimal geometry with a lead absorber between detectors suppresses contribution of the distorted coincidences down to 1% providing sufficiently high count rate of true events. (C) 2014 Elsevier B.V. All rights reserved.

【 授权许可】

Free