  In view of recent experiments in ultracold atomic systems, the
photoassociation of Efimov trimers, composed of three identical bosons, is
studied utilizing the multipole expansion. We study both the normal hierarchy
case, where one-body current is dominant, and the strong hierarchy case,
relevant for photoassociation in ultracold atoms, where two-body current is
dominant. For identical particles in the normal hierarchy case, the leading
contribution comes from the r^2 s-mode operator and from the quadrupole d-mode
operator. The s-mode reaction is found to be dominant at low temperature, while
as the temperature increases the d-mode becomes as significant. For the strong
hierarchy case, the leading contribution comes from a 2-body s-wave {\delta}
operator. In both cases log periodic oscillations are found in the cross
section. For large but finite scattering length the amplitude of the
oscillations becomes larger in comparison to infinite scattering length case.
We apply our theory to photoassociation of 7Li ultracold atoms and show a good
fit to the available experimental results.
