论文标题
阻抗和不稳定性
Impedances and Instabilities
论文作者
论文摘要
引入了尾流场和阻抗的概念，以描述一堆带电颗粒与其在粒子加速器中的环境的电磁相互作用。唤醒场可以在光束上行动并导致不稳定性，这可能会限制每束，总电流甚至两者的可实现电流。一些典型的示例用于说明唤醒功能及其基本属性。然后解释了唤醒场或阻抗的频域视图，并得出了阻抗的基本特性。使用等效电路模型说明了腔模式的阻抗。在刚性梁近似中处理尾流效果与重要光束参数的关系。采用了几个例子来说明几何形状和真空室对阻抗的材料特性的影响。最后，给出了基于梁头尾模型的梁不稳定性的基本介绍。
The concepts of wake fields and impedance are introduced to describe the electromagnetic interaction of a bunch of charged particles with its environment in an particle accelerator. The wake fields can act back on the beam and lead to instabilities, which may limit the achievable current per bunch, the total current, or even both. Some typical examples are used to illustrate the wake function and its basic properties. Then the frequency-domain view of the wake field or impedance is explained, and basic properties of the impedance are derived. The impedance of a cavity mode is illustrated using an equivalent circuit model. The relation of wake field effects to important beam parameters is treated in the rigid beam approximation. Several examples are employed to illustrate the impact of the geometry and the material properties of the vacuum chamber on the impedance. Finally, a basic introduction to beam instabilities based on a head tail model of the beam is given.
