Abstract:
We generalize the wave-packet continuum discretization method previously
developed for the scattering problem to the three-body system. For each
asymptotic channel, we construct a basis of three-body wave packets
given by square-integrable functions. We show that the projections of
the channel resolvents on the subspace of three-body wave packets are
determined by diagonal matrices, whose eigenvalues we find explicitly. We
express the amplitudes of $2\to 2$ processes explicitly in terms of
"wave-packet" finite-dimensional projections of the full resolvent. To illustrate
our formalism, we calculate the differential cross section of elastic
deuteron scattering on a heavy nucleus above the three-body breakup
threshold and the $s$-wave quartet $(n-d)$-scattering amplitude.
The results of the calculations agree well with the results obtained by other
methods. In terms of complexity, the proposed scheme for solving
the three-body scattering problem is comparable to solving a similar problem
for bound states.
Keywords:quantum scattering theory, few-body system, discretization of the continuum.