STABILIZATION OF BEAM INTERACTION IN THE TESLA LINEAR

Vertical beam offsets at the interaction point will degrade the luminosity (3.4 · 10 34 cm −2 s −1 ) in the TESLA linear collider. In order to limit the luminosity loss to 10% per bunch crossing the electron (e − ) and positron (e + ) beams must interact with an offset and angle of less than 1/10 of the beam size and the angular divergence respectively. The required stabilization of the beam interaction will be provided on a bunch to bunch basis by two feedback systems. One system, located upstream of the vertical chromatic correction system, controls the beam angle. The second system placed at the interaction region steers the two beams into collision using the beam-beam deflection method. This paper describes the feedback designs and presents simulation results. Design modifications necessary for the e − e − mode are briefly discussed.