Small horizontal emittance in the TESLA damping ring

The present TESLA damping ring is designed for a normalized horizontal emittance of 8×10−6 m. γ–γ collisions at the TESLA linear collider will benefit from a further decrease of the horizontal emittance. This paper reviews the processes which limit the horizontal emittance in the damping ring. Preliminary estimates on the smallest horizontal emittance for the present TESLA damping ring design as well as an ultimate limit of the emittance reachable with the TESLA damping ring concept will be given.