Longitudinal bunch shaping is gaining increasing attention due to the large impact it has on modern accelerators. The existing methods for controlling the density profile fall into three categories: laser shaping, emittance exchange, or correlations between the energy and one of the other coordinates. These methods require either (i) dispersive elements (e.g., dipole magnet), which generates coherent synchrotron radiation, or (ii) shaping near the cathode, which can distort the profile due to space-charge effects. These collective effects significantly decrease shaping quality as the bunch charge increases. None of the existing methods are currently capable of shaping high-charge bunches. In this paper, we introduce a transverse deflecting cavity-based shaping method to avoid the impact of collective effects on the shaping process. In this method, a transverse deflecting cavity introduces the $z-x$ correlation, and a transverse mask tailors the longitudinal density profile. This method provides high-quality shaping regardless of charge level and preserves the beam quality.

中文翻译：

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使用横向偏转腔的无相干同步辐射无辐射纵向束整形

纵向束成形因其对现代加速器的巨大影响而日益受到关注。用于控制密度分布的现有方法分为三类：激光整形，发射交换或能量与另一个坐标之间的相关性。这些方法需要（i）产生相干同步辐射的色散元件（例如，偶极磁体），或（ii）在阴极附近整形，由于空间电荷效应，该形状会扭曲轮廓。这些聚集效应会随着束料的增加而显着降低成形质量。当前，任何现有方法都无法塑造高电荷束。在本文中，我们介绍了一种基于横向偏转腔的成形方法，以避免集体效应对成形过程的影响。用这种方法$ž-X$相关性，横向掩膜可调整纵向密度分布。无论电荷量高低，该方法都能提供高质量的整形效果，并保持光束质量。