  The cross section of the 16O(a,g)20Ne capture reaction is analyzed at low
energies where the direct capture mechanism is dominant. For temperatures below
T9 = 0.2 the resulting astrophysical reaction rate is about a factor of two
higher than in a recent compilation whereas the energy dependence of the
astrophysical S-factor and the branching ratios to the 20Ne bound states are
very similar to previous calculations. The validity of the widely used detailed
balance theorem for the inverse 20Ne(g,a)16O photodisintegration rate is
confirmed for the special case of high-lying first excited states.
