Beam behavior and vacuum aspects in the LURE storage rings

A short description of the LURE storage rings, DCI and Super-ACO, in relation to vacuum and beam lifetime is first given. The newly proposed 2.15 GeV low emittance ring, SOLEIL, is presented and discussed. A beamline for the photon stimulated desorption studies carried out at DCI in collaboration with the CERN AT--VA group is also described. Finally, the results of an experiment carried out at Super-ACO, in view of detecting the instability of a positron bunched beam in interaction with the wake field of positive ions are presented. The effect is greatly enhanced due to an argon pressure rise obtained by switching off the ion pumps. A strong wall pumping effect of the ions accelerated by the positron beam is reported. This was taken into account to optimize the best conditions for observing the instability. Several runs are taken with the beam being stable. These results confirm the beam and vacuum parameters expected in the φ, τc and B-factory projects. Still, it calls for a comprehensive comparison between the theoretical predictions and the present experimental results. (author). 3 refs., 3 figs