LUMINOSITY AND DISRUPTION IN e � e � LINEAR COLLIDERS

We present an empirical analytic approximation for the luminosity \de-enhancement" factor HD in e e collisions, as a function of the disruption parameters Dx, Dy, the hour-glass parameters Ax, Ay, and the beam aspect ratio R x= y. We treat Gaussian beams with essentially arbitrary aspect ratio, assuming only that the vertical beam size is less than or equal to the horizontal beam size and that the vertical beta function is less than or equal to the horizontal beta function. Presented at Worldwide Study on Physics and Experiments with Future Linear e+eColliders, April 28 May 5, 1999, Sitges (Barcelona), Spain Work supported by Department of Energy contract DE{AC03{76SF00515. LUMINOSITY AND DISRUPTION IN e e LINEAR COLLIDERS K.A. Thompson and P. Chen Stanford Linear Accelerator Center, P.O.Box 4349, Mail Stop 26, Stanford, CA 94309, USA We present an empirical analytic approximation for the luminosity \deenhancement" factor HD in e e collisions, as a function of the disruption parameters Dx, Dy, the hour-glass parameters Ax, Ay, and the beam aspect ratio R x= y. We treat Gaussian beams with essentially arbitrary aspect ratio, assuming only that the vertical beam size is less than or equal to the horizontal beam size and that the vertical beta function is less than or equal to the horizontal beta function.