Beam-beam performance as a function of beta v* at CESR

The beam-beam tune shift parameter for beams colliding at a single interaction point was measured for several values of the vertical beta minimum. The authors report linear tune shift parameter as a function of current for 1 cm< beta /sub v/*<10 cm. Electrostatic separators are used to horizontally separate beams at all but one crossing point. The quadrupole lattice is characterized by zero dispersion at the interaction point, horizontal beta /sub h/*=1 m, and horizontal and vertical tunes of Q/sub h/ approximately 8.6 and Q/sub v/ approximately 9.64 respectively. The two sets of measurements correspond to operation before and after the single interaction point conversion of CESR (Cornell Electron Storage Ring).<>