At a background gas pressure of 10 nTorr, beam lifetimes of only a few hours are expected. We find that more » the single-bunch instabilities should not lead to difficulty, and that the emittance growth is essentially negligible. In addition, we examine the possibility of emittance growth from intrabeam scattering and calculate the beam lifetime from both Touschek and gas scattering. Both single-bunch and coupled-bunch instabilities are described and their effects are estimated based upon an example machine design (APIARY-IV). In this paper we consider the influence of collective effects on the machine performance most of our findings are generic,'' in the sense that they depend rather weakly on the details of the machine design. The design of a high-luminosity electron-positron collider to study B physics is a challenging task from many points of view. In terms of collective effects, it does not appear that there are any fundamental problems standing in the way of successfully designing and building a high-luminosity B factory. Thus, a powerful feedback system will be required. Multibunch growth rates are very severe, even when using an optimized RF system consisting of single-cell, room-temperature RF cavities with geometrical shapes typical of superconducting cavities. The design of a high-luminosity electron-position collider to study B physics is a challenging task from many points of view. Nonetheless, it does not appear that there are any fundamental problems that stand in the way of successfully designing and building such a high-luminosity B-Factory. Even then, a powerful feedback system will likely be required. There appear to be significant benefits to a radically different rf system design, either utilizing superconducting single-cell rf cavities, or cavities with equivalent geometrical shapes but operated at room temperature. With a standard PEP-like multicell rf system, multibunch growth rates are very severe, especially in the longitudinal plane. Even this lifetime is likely to require an innovative design for the vacuum system to maintain a pressure of 10 nTorr in the presence of a circulating electron or positron beam of approximately 1 A. At a background gas pressure of 10 nTorr, beam lifetimes of only a few hours are expected, which will place a burden on the injection system if a high average luminosity is to be maintained. We find that the single-bunch instabilities should not lead to difficulty, and that the emittance growth is essentially negligible. Based upon an example machine design (APIARY-II), we investigate single-bunch thresholds for the longitudinal microwave and transverse mode-coupling instabilities, examine the possibility of emittance growth from intrabeam scattering, calculate the beam lifetime from Touschek scattering and gas scattering, and estimate the growth rates for both longitudinal more » and transverse coupled-bunch instabilities. The design of a high-luminosity electron-positron collider to study B-physics is a challenging task from many points of view.
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