Precision measurement of the vacuum from the contribution of Delbrck scattering of -rays off nuclei

原子核から線によるデルブリュック散乱の貢献での高精密真空測定

Koga, J. K.; 早川 岳人

Koga, J. K.; Hayakawa, Takehito

Four processes are known to contribute to the scattering of -rays off nuclei. Since Delbrck scattering occurs from the polarization of the vacuum generated by virtual electron-positron pairs in the Coulomb field of the nucleus, its measurement can give us information about the properties of the vacuum. Although active research on Delbrck scattering stopped in the early 1990's, there is a renewed interest in its measurement. We will present our calculations of the Delbrck scattering, compare them with tabulated values, and show regimes where its contribution can be sufficiently isolated from the other processes and precisely measured. Deviations from the theoretical calculations would indicate the need for new physics beyond the Standard Model.