  Ions of the isomer $^{229m}$Th are a topic of high interest for the
construction of a "nuclear clock" and in the field of fundamental physics for
testing symmetries of nature. They can be efficiently captured in Paul traps
which are ideal for performing high precision quantum logic spectroscopy.
Trapping and identification of long-lived $^{232}$Th$^{+}$ ions from a laser
ablation source was already demonstrated by the TACTICa collaboration on
Trapping And Cooling of Thorium Ions with Calcium. The $^{229m}$Th is most
easily accessible as $\alpha$-decay daughter of the decay of $^{233}$U. We
report on the development of a source for slow Th ions, including $^{229(m)}$Th
for the TACTICa experiment. The $^{229(m)}$Th source is currently under
construction and comprises a $^{233}$U monolayer, from which $^{229(m)}$Th ions
recoil. These are decelerated in an electric field. Conservation of the full
initial charge state distribution of the $^{229(m)}$Th recoil ions is one of
the unique features of this source. We present ion-flight simulations for our
adopted layout and give a final design. This source will provide Th ions in
their original charge state at energies suitable for capture in a linear Paul
trap for spectroscopy investigations.
