This paper provides a theoretical complement to the experimental measurement
of the population of excited dμ(2s) and dμ(1s) atoms in a deuterium. The
population of these atoms plays an important role in a muon catalyzed fusion
cycle. Symmetric and non-symmetric muonic molecular ions have been
predicted to form in excited states in collisions between excited muonic
atoms and hydrogen molecules. One example is the ddμ∗, which is a
muonic deuterium–deuterium symmetric ion in excited state and is initially
produced in the interaction of dμ(2s) atoms with deuterium nuclei. Our
calculations interpret the experimental findings in terms of the so-called sidepath
model. This model essentially deals with the interaction mentioned
above in which the ddμ∗ ion undergoes Coulomb de-excitation where the
excitation energy is shared between a dμ(1s) atom and one deuterium. The
structure of ddμ∗ is studied here using the numerical, variational method and
the given wavefunctions. Few resonance energies for ddμ∗ molecular states are
calculated belowthe 2s threshold. Formore precise assessment of the reliability
of the given wavefunctions, the nucleus sizes and Coulomb decay rates for the
zeroth, first and second vibrational meta-stable states of the mentioned ion are
also calculated. The obtained results are close to those previously reported.
The advantage of the given method over previous methods is that the used
wavefunction has only two terms, which simplifies the calculations with the
same results as those from the complicated coupled rearrangement channel
method with a Gaussian basis set. These energies are the base data required
for size, formation and decay rate calculations of the ddμ∗ ion.