Beam stability studies and improvements at Aladdin

Recent improvements in beam position stability at Aladdin, the 1 GeV electron storage ring at the Synchrotron Radiation Center, are reported. Stabilizing the beam position monitors (BPM's), in conjunction with the use of a global feedback system, keeps the beam position within /spl plusmn/3 /spl mu/m of its starting value during a user fill. Relocation of transformers and the dipole power supply choke have made substantial reductions in the 60 and 720 Hz motions of the electron beam, allowing a broader scope to the infrared experimental program. Work on stabilizing the synchrotron radiation source characteristics under various operating conditions is presented. Studies of weak resonances near the standard operating tune are leading to the use of closed loop tune control to maintain beam size stability. Lattice corrections employed during the scanning of undulators keep the source sizes fixed down to the 2% level. Future plans for improved optical beam position and size monitors, renovation of the BPM electronics, implementation of a hydrostatic leveling system, and temperature monitoring of the ring components is also presented.