Serach for 5.5 MeV solar axions with the Borexino detector

The sensitivity of the Borexino large scintillation detector was determined for search for axions with an energy of 5.5 MeV produced in the nuclear reaction $p+d\to{}^3\mathrm{He}+A$ in the Sun through the Compton process and the conversion of an axion into a photon in the solar core field . Basing on the measured Borexino spectrum, new upper limits have been established for the product of the coupling constants of the axion with electrons and nucleons $|g_{Ae}g_{AN}^3|\le4.6\cdot10^{13}$ and with a photon and nucleons $|g_{A\gamma}g_{AN}^3|\le3.6\cdot10^{-11}$ GeV$^{-1}$, both limits are given for 90% confidence level.