High energy photon-neutrino elastic scattering

Abstract

The one-loop helicity amplitudes for the elastic scattering process ${\hat{I}}^3\hat{I}½\to {\hat{I}}^3\hat{I}½$ in the Standard Model are computed at high center of mass energies. A general decomposition of the amplitudes is utilized to investigate the validity of some of the key features of our results. In the center of mass, where $\sqrt{s}=2\ddot{I}‰$, the cross section grows roughly as $\ddot{I}{‰}^6$ to near the threshold for $W$-boson production, $\sqrt{s}=m_W$. Although suppressed at low energies, we find that the elastic cross section exceeds the cross section for ${\hat{I}}^3\hat{I}½\to {\hat{I}}^3{\hat{I}}^3\hat{I}½$ when $\sqrt{s}>13$ GeV. We demonstrate that the scattered photons are circularly polarized and the net value of the polarization is non-zero. Astrophysical implications of high energy photon-neutrino scattering are discussed.

9 pages, 7 figures, RevTeX4