Study of high-energy photons polarization in Compton scattering using the J-PET detector system
Supervisor: dr Magdalena Skurzok
abstract
Defence year: 2023
The purpose of this work is the study of the high-energy photons polarization in Compton scattering using the Jagiellonian Positron Emission Tomography scanner (J-PET), more specifically finding the distribution of an angle between incoming and scattered photons polarization planes which opens the door for the polarization studies. Although polarization itself is a well studied phenomenon, until now it was only possible to investigate it in a narrow range of energies, using optical methods. J-PET detector, due to its unique construction, allows the registration of high-energetic gamma quanta emitted by the radioactive source and
coming from the electron-positron annihilation and also their multiple scatterings. It enables to determine the direction of photons momentum vectors, thus the directions of their polarization. In this work three main types of analysis were performed, differing in the energy and origin of the incoming photons: (i) electron-positron annihilation photons, with the energy of 511 keV, (ii) already scattered photons, found between two interactions in the detector with an unknown energy, (iii) 22Ne de-excitation photons, with the energy of 1275 keV. Future measurements of the polarization will allow deeper understanding of the other phenomena,
such as quantum entanglement or testing discrete symmetries in the leptonic sector.
