The PEP-II Interaction Region with the BaBar Solenoid”, SLAC-pub-8299, e+eFactories 99

M. Sullivan
Y. Cai
M. Donald
F. J. Decker
S. Ecklund
A. S. Fisher
L. Henderson
T. Himel
M. Minty
Y. Nosochkov
J. Seeman
U. Wien

Publication date

January 1999

Abstract

In the spring of 1999, the BaBar detector rolled onto the beam line in the PEP-II[1] interaction region (IR). The presence of the detector solenoidal field significantly al-ters the behavior of the accelerator. Both beams, the high-energy beam (HEB) and the low-energy beam (LEB), are affected. The beams become coupled in the xy plane and the orbits are changed. We discuss these and other changes brought about by the solenoidal field of the Ba-Bar detector. 1 THE INTERACTION REGION The PEP-II interaction region[2], shown in figure 1, em-ploys two strong horizontal bending magnets (B1) located 21 cm from the IP to bring the beams into a head-on collision. On either side of the interaction point (IP), th