Does Sub-Barrier Bremsstrahlung in -Decay of 210Po Exist?

A quantum mechanical model for the description of the alpha-decay of heavynuclei with accompanying photons emission is presented. The model is based on aquantum mechanical one-particle model of alpha-decay through a decay barrier.The bremsstrahlung spectrum calculation employs multipole expansion of thevector potential of the Coulomb field of the daughter nucleus and takes intoaccount the dependence on the angle between the directions of thealpha-particle propagation and the photon emission. Spectra of 210Po areobtained for the angles 25 and 90, and the best agreement with the experimentaldata in the 90 case in a comparison with other existing models is achieved. From the angular analysis, the model gives monotonic behavior of thebremsstrahlung spectrum for any value of the angle. We find that sub-barrierphoton emission (i. e. bremsstrahlung photon emission during alpha-particletunneling through decay barrier) exists but gives a small contribution to thetotal bremsstrahlung spectrum.Comment: reference correction