  A new approach to observe the radiative decay of the $^{229}$Th nuclear
isomer, and to determine its energy and radiative lifetime, is presented.
Situated at a uniquely low excitation energy, this nuclear state might be a key
ingredient for the development of a nuclear clock, a nuclear laser and the
search for time variations of the fundamental constants. The isomer's $\gamma$
decay towards the ground state will be studied with a high-resolution VUV
spectrometer after its production by the $\beta$ decay of $^{229}$Ac. The novel
production method presents a number of advantages asserting its competitive
nature with respect to the commonly used $^{233}$U $\alpha$-decay recoil
source. In this paper, a feasibility analysis of this new concept, and an
experimental investigation of its key ingredients, using a pure $^{229}$Ac ion
beam produced at the ISOLDE radioactive beam facility, is reported.
