Gao Q, Ha G, Jing C, Antipov S P, Power J G, Conde M, Gai W, Chen H, Shi J, Wisniewski E E, Doran D S, Liu W, Whiteford C E, Zholents A, Piot P, Baturin S S
Department of Engineering Physics, Tsinghua University Beijing, Beijing 100084, People's Repubic of China.
Key Laboratory of Particle and Radiation Imaging, Tsinghua University, Ministry of Education, Beijing 100084, People's Repubic of China.
Phys Rev Lett. 2018 Mar 16;120(11):114801. doi: 10.1103/PhysRevLett.120.114801.
Collinear wakefield acceleration has been long established as a method capable of generating ultrahigh acceleration gradients. Because of the success on this front, recently, more efforts have shifted towards developing methods to raise the transformer ratio (TR). This figure of merit is defined as the ratio of the peak acceleration field behind the drive bunch to the peak deceleration field inside the drive bunch. TR is always less than 2 for temporally symmetric drive bunch distributions and therefore recent efforts have focused on generating asymmetric distributions to overcome this limitation. In this Letter, we report on using the emittance-exchange method to generate a shaped drive bunch to experimentally demonstrate a TR≈5 in a dielectric wakefield accelerator.
共线尾场加速早已被确立为一种能够产生超高加速梯度的方法。由于在这方面取得的成功，近来，更多的努力转向开发提高变比（TR）的方法。这个品质因数被定义为驱动束团后方的峰值加速场与驱动束团内部的峰值减速场之比。对于时间对称的驱动束团分布，TR总是小于2，因此近来的努力集中在产生非对称分布以克服这一限制。在本信函中，我们报告了利用发射度交换方法产生一个成形的驱动束团，从而在介质尾场加速器中通过实验证明TR≈5 。
