Two-photon interactions with Majorana fermions
arXiv:1706.05071 · doi:10.1103/PhysRevD.94.093010
Abstract
Because Majorana fermions are their own antiparticles, their electric and magnetic dipole moments must vanish, leaving the anapole moment as their only static electromagnetic property. But the existence of induced dipole moments is not necessarily prohibited. Through a study real Compton scattering, we explore the constraints that the Majorana fermion's self-conjugate nature has on induced moments. In terms of the Compton amplitude, we find no constraints if the interactions are separately invariant under charge conjugation, parity, and time reversal. However, if the interactions are odd under parity and even under time reversal, then these contributions to the Compton amplitude must vanish. We employ a simple model to confirm these general findings via explicit calculation of the Majorana fermion's polarizabilities. We then use these polarizabilities to estimate the cross-section for -wave annihilation of two Majorana fermions into photons. The cross-section is larger than a naïve estimate might suggest.
References in corpus (11)
- Collective neutrino flavor transitions in supernovae and the role of trajectory averaging
- Multiple Spectral Splits of Supernova Neutrinos
- The multi-angle instability in dense neutrino systems
- Analysis of Collective Neutrino Flavor Transformation in Supernovae
- Adiabaticity and spectral splits in collective neutrino transformations
- Neutrino Mass Hierarchy and Stepwise Spectral Swapping of Supernova Neutrino Flavors
- How Dark Are Majorana WIMPs? Signals from MiDM and Rayleigh Dark Matter
- Simple Picture for Neutrino Flavor Transformation in Supernovae
- Identifying neutrino mass hierarchy at extremely small theta(13) through Earth matter effects in a supernova signal
- Mu-tau neutrino refraction and collective three-flavor transformations in supernovae
- CP-violation in Compton scattering