CONCLUSION

In conclusion, we sum up the results obtained here:

• the electromagnetic properties of Dirac and Majorana massless neutrinos are presented by the TDM of the order of $e\cdot\left(10^{-33}-10^{-34}\right)$ cm$^2$;
• for massive neutrinos the toroid dipole moment is
  
  $$T\Biggr\vert _{m_\nu} = T\Biggr\vert _{m_\nu=0}+ {\cal O}\left(\frac{m_\nu^2}{m_W^2}\right);$$
  
  

• the toroid interactions are a part of radiative corrections to the scattering of neutrinos on electrons, quarks and nuclei both in the vacuum and in the medium;
• the above mentioned effects can manifest themselves in numerous astrophysical and cosmological situations. Among them are neutrino propagation through the solar interior and young supernova envelopes, neutrino radiation of accreting neutron stars and black holes, where inhomogeneous vortex magnetic fields can have large values, high-energy neutrino generation due to heavy particle emission and acceleration by saturated superconducting cosmic strings or due to cusp radiation from ordinary cosmic strings etc., and the toroid interactions of neutrinos should be taken into account in each of them;
• $\sigma^{\gamma Z}_{\rm tor}$ and $\sigma^\gamma_{\rm tor}$ are maximal at low energies ($\sim 1$ MeV);
• neutrinos can produce the Vavilov-Cherenkov and transition radiations due to its TDM.