Bremsstrahlung Emission During Alpha-Decay Of Ra-226

We obtained the spectrum of probability of the bremsstrahlung emission accompanying the alpha-decay of Ra-226 (E-alpha = 4.8 MeV) by measuring the alpha-gamma coincidences and using the model presented in our previous study on the alpha-decay of Po-214 (E-alpha = 7.7 MeV). We compare the experimental data with the quantum mechanical calculation and find a good agreement between theory and experiment. We discuss the differences between the photon spectra connected with the alpha-decay of the Ra-226 and Po-214 nuclei. For the two mentioned nuclei, we analyze the bremsstrahlung emission contributions from the tunneling and external regions of the nucleus barrier into the total spectrum, and we find the destructive interference between these contributions. We also find that the emission of photons during tunneling of the alpha-particle gives an important contribution to the bremsstrahlung spectrum in the whole E-gamma energy range of the studied Ra-226 nucleus.