Simulation studies of annihilation-photon\u2019s polarisation via Compton scattering with the J-PET tomograph

N Krawczyk,T Kozik ,B Jasińska ,K Rakoczy,K Dulski ,M Pawlik-Niedźwiecka ,E Kubicz ,B Zgardzińska ,Marcin Zieliński ,D Kisielewska ,A Gajos ,W Krzemień ,N Gupta-Sharma ,Beatrix C Hiesmayr ,M Mohammed ,G Korcyl ,C Curceanu ,R Y Shopa,M Pałka ,Sushil Sharma ,M Gorgol ,J Chhokar ,Z Rudy ,Sz Niedźwiecki ,Shivani ,P Kowalski ,L Raczyński ,W Wiślicki ,E Czerwiński ,J Raj,M Skurzok ,P Moskal

doi:10.1007/s10751-019-1629-0

Abstract

J-PET is the first positron-emission tomograph (PET) constructed from plastic scintillators. It was optimized for the detection of photons from electron-positron annihilation. Such photons, having an energy of 511 keV, interact with electrons in plastic scintillators predominantly via the Compton effect. Compton scattering is at most probable at an angle orthogonal to the electric field vector of the interacting photon. Thus registration of multiple photon scatterings with J-PET enables to determine the polarization of the annihilation photons. In this contribution we present estimates on the physical limitation in the accuracy of the polarization determination of 511 keV photons with the J-PET detector.

Highlights

J-positron-emission tomograph (PET) is a multipurpose detector designed for the development of medical imaging [1,2,3,4,5], for studies of discrete symmetries in decays of positronium atoms [6], as well as for investigations of multipartite quantum entanglement of photons originating from positronium annihilation [7,8,9]
− sin2 θ where E is the energy of initial photon, E is the energy of photon after scattering, θ is the Compton scattering angle and η is the angle between scattering and polarization planes
The J-PET tomograph built from plastic scintillators enables measurements of the polarization of photons at an event-by-event basis

Summary

Introduction

J-PET is a multipurpose detector designed for the development of medical imaging [1,2,3,4,5], for studies of discrete symmetries in decays of positronium atoms [6], as well as for investigations of multipartite quantum entanglement of photons originating from positronium annihilation [7,8,9]. Position and time of the interaction in the detector material are determined based on the arrival time of light signals at both ends of the scintillator strips. Photons from the e+e− annihilation interact in plastic scintillators predominantly via the Compton effect and in the J-PET detector a few percent of them undergo secondary scatterings. We discuss the physical limits of the accuracy for the polarization determination of annihilation photons via Compton scattering

Compton scattering and Klein-Nishina formula

E E sin2 θ

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Summary