Beam Based Solenoid Compensation for the PEP-II
نویسنده
چکیده
Commissioning the compensation system of the solenoid in the BaBar detector presents a challenging problem due to the complexity of the system, which uses twelve normal quadrupoles and twelve skew quadrupoles in each ring. The setting of these skew quadrupoles needs to be readjusted according to the machine optical parameters since the machines always have some unknown errors. In this paper, we will describe a beam based method to match the coupling and optics in the interaction region to compensate for the optical e ects due to the solenoid. The method has been successfully used to nd the wrong polarities and the wrong scaling factor of the skew quadrupoles in the early stage of the commissioning. It is being re ned to set the skew quadrupoles in the machines in order to reduce the beam size at the interaction point and improve the luminosity of PEP-II. Submitted to e+eFactories'99, September 21th 24th 1999, KEK, Tsukuba, Japan. Work supported by the Department of Energy under Contract No. DE-AC03-76SF00515. Beam Based Solenoid Compensation for the PEP-II Yunhai Cai, Stanford Linear Accelerator Center, USA
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