||Possiblity for measuring Delbrueck Scattering in the sub-MeV range using polarized gamma-ray photons
Kevin Koga, JamesHayakawa, Takehito
Delbrueck scattering is the elastic scattering of gamma-rays off the Coulomb field of nuclei due to the formation of virtual electron-positron pairs from vacuum. The elastic scattering of gamma-ray sources from atoms is a coherent sum of Rayleigh, Thomson, Giant Dipole resonances and Delbrueck scattering and as energies go below the MeV level the Rayleigh scattering becomes more and more dominant. Previous experiments performed using unpolarized gamma-ray sources have shown the effects of Delbrueck scattering at photon energies as low as 889 keV. However, linearly polarized gamma-rays via laser Compton backscattering sources having high flux offer the possibility to measure Delbrueck scattering with a higher degree of accuracy at these and even lower energies. Here, we show that by properly choosing the scattering angles and polarization of the gamma-rays one can measure Delbrueck scattering in the sub-MeV range. By choosing a high Z material we will present the time necessary using the new gamma-ray sources to measure Delbrueck scattering accurately.
Light driven Nuclear-Particle physics and Cosmology 2017