Precision Measurement of Delbrück Scattering via Laser Compton Scattered γ-rays

8th International Conference on Inertial Fusion Sciences and Applications

Koga, J.K.^1 ; Hayakawa, T.^2

Quantum Beam Science Dir., Japan Atomic Energy Agency, Kizugawa, Kyoto, Japan^1

Quantum Beam Science Dir., Japan Atomic Energy Agency, Ibaraki-Tokai, Japan^2

关键词: Anomalous magnetic moments;    Electron-positron pairs;    Energy recovery linac;    Laser Compton scattering;    Neutron capture reaction;    Precision measurement;    Scattering cross section;    Theoretical calculations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/688/1/012050/pdf
DOI  :  10.1088/1742-6596/688/1/012050

来源: IOP

【 摘 要 】

Precision measurements such as the muon anomalous magnetic moment have indicated deviations from the standard model and have in turn prompted higher precision theoretical calculations. Delbrück scattering is the scattering of photons off the Coulomb field of nuclei via virtual electron-positron pairs and has been measured using γ-rays from radioactivities and following neutron capture reactions. However, because low flux γ-rays from nuclear transitions have been used in the low photon energy regime fairly large uncertainty exists in the data. In addition, due to the complexity and time consuming nature of the theoretical calculation the scattering cross sections are obtained from tables with interpolation between the tabular values. In recent years high flux γ-ray sources via laser Compton scattering (LCS) using energy-recovery linacs have been proposed. These sources allow measuring the Delbrück scattering with high precision. We will present our own independent calculations for the scattering cross section and show what precision can be obtained using the new LCS γ-ray sources in the low photon energy regime.