Solar Neutrino Background in Neutrinoless double beta-decay searching   for experiments
  Background of germanium and xenon detectors due to the elastic scattering of $^{8}B$ solar neutrinos on electrons have been calculated. The background is 4.6 \times $10^{-4}$ counts/(keV$\cdot t\cdot$y) that defines the sensitivity of double beta-decay experiments at a level $T^{0\nu\beta\beta}_{1/2} \approx 4\times$10^{27}$ {yr} and it corresponds to effective majorana mass $ \mid < m_{\nu_e}>\mid \approx 23.5$ meV. This limit after a half of one year of measurements for 10 tons natural Xe detector will be obtained. 
Alexander A. Klimenko