We study the time evolution of the typical nuclear reactor antineutrino
energy spectrum during reactor ON period and the decay of the residual
antineutrino spectrum after reactor is stopped. We find that relevant
variations of the soft recoil electron spectra produced via weak and magnetic
νe,e scattering process can play a signigicant role in
the current and planned searches for the neutrino magnetic moment at reactors.Comment: 4 pages LaTeX 2.09. 4 PS figures. Resume of seminar talks given at
Kurchatov Institute, March 1999