Injection and acceleration with physics optics in LEP

Up to now injection into LEP has been done using a dedicated injection optics, with a vertical b*v = 21 cm. After accelerating to higher energies a progressive optics change is made with beam to the Œphysics¹ optics, where b*v = 5 cm. The use of synchrotron injection as the normal means of accumulation in LEP has opened up the possibility of injecting directly into the Œphysics¹ optics. This has many advantages ranging from an easier operation, including a faster turnaround from injection to physics conditions, to allowing more flexibility in the optics design and matching. Results from machine development sessions are presented showing that there is no fundamental reason for not implementing this scheme. Potential drawbacks and limitations, especially for the maximum accumulated beam current are, however, discussed.