The PLS-II is a third-generation light source; it has been operating since 2011. It has a double-bend structure with non-zero dispersion along the straight section. Here, we assess three proposed upgrades to the PLS-II. First, we evaluate use of a canted insertion device beamline to increase the number of beamlines. Second, we evaluate the consequences of upgrading the bending magnet to a superbend magnet; the change doubles the strength of the bending field and increases the critical energy from 8.7 keV to 17 keV. Finally, a short-bunch mode for time-resolved experiments is studied; the goal is to achieve a bunch length of 5 ps rms by using a low-alpha mode and increasing the RF gap voltage.

中文翻译：

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升级到 PLS-II 存储环的可行性研究

PLS-II 是第三代光源；它从2011年开始运行。它具有沿直线段非零色散的双弯曲结构。在这里，我们评估了对 PLS-II 的三个建议升级。首先，我们评估使用倾斜插入设备光束线来增加光束线的数量。其次，我们评估了将弯曲磁铁升级为超弯曲磁铁的后果；这种变化使弯曲场的强度加倍，并将临界能量从 8.7 keV 增加到 17 keV。最后，研究了一种用于时间分辨实验的短束模式；目标是通过使用低阿尔法模式并增加 RF 间隙电压来实现 5 ps rms 的束长度。