  We report on an injection feedback scheme for the ThomX storage ring project.
ThomX is a 50-MeV-electron accelerator prototype which will use Compton
backscattering in a storage ring to generate a high flux of hard X-rays. Given
the slow beam damping (in the ring), the injection must be performed with high
accuracy to avoid large betatron oscillations. A homemade analytic code is used
to compute the corrections that need to be applied before the beam injection to
achieve a beam position accuracy of a few hundred micrometers in the first beam
position monitors (BPMs). In order to do so the code needs the information
provided by the ring's diagnostic devices. The iterative feedback system has
been tested using MadX simulations. Our simulations show that a performance
that matches the BPMs' accuracy can be achieved in less than 50 iterations in
all cases. Details of this feedback algorithm, its efficiency and the
simulations are discussed.
