Imaging laser-wakefield-accelerated electrons using miniature magnetic quadrupole lenses
Imaging laser-wakefield-accelerated electrons using miniature magnetic quadrupole lenses
复制标题
DOI：
10.1103/physrevstab.14.052801
复制
发表时间：
2011-05
影响因子：
--
通讯作者：
R. Weingartner;M. Fuchs;A. Popp;S. Raith;S. Becker;S. Chou;M. Heigoldt;K. Khrennikov;J. Wenz;T. Seggebrock;B. Zeitler;Z. Major;J. Osterhoff;F. Krausz;S. Karsch;F. Grüner
中科院分区：
文献类型：
--
作者：
R. Weingartner;M. Fuchs;A. Popp;S. Raith;S. Becker;S. Chou;M. Heigoldt;K. Khrennikov;J. Wenz;T. Seggebrock;B. Zeitler;Z. Major;J. Osterhoff;F. Krausz;S. Karsch;F. Grüner
能量扩散、光束发散和指向波动的改善是当前电子的激光尾流场加速领域面临的一些主要挑战。我们通过使用场梯度为500 T=m的微型磁四极透镜在电子束产生后操纵电子束来解决这些问题。通过成像电子束的偶极磁铁谱仪的光谱分辨率可以显着增加，导致在190兆电子伏的测量能量分散下降到1.0%的均方根。不同电子能量的聚焦证明了透镜系统的可调谐性，并且可以用于过滤掉偏离目标的能量，以便进一步减小能量扩散。通过准直光束，在距离源1 m处测量的光束的拍摄到拍摄的空间稳定性提高了5倍。此外，通过有意地横向偏移四极透镜，电子束可以在任何方向上被操纵几毫拉德。这些方法可以在仍然保持束的超短聚束持续时间和低发射度的同时实施，并且除了能量过滤器中的不期望的电子能量之外，没有任何电荷损失。这种可靠和紧凑的控制激光尾场加速电子束是独立的加速器本身，允许立即应用目前可用的光束。
The improvement of the energy spread, beam divergence, and pointing fluctuations are some of the main challenges currently facing the field of laser-wakefield acceleration of electrons. We address these issues by manipulating the electron beams after their generation using miniature magnetic quadrupole lenses with field gradients of � 500 T=m. By imaging electron beams the spectral resolution of dipole magnet spectrometers can be significantly increased, resulting in measured energy spreads down to 1.0% rms at 190 MeV. The focusing of different electron energies demonstrates the tunability of the lens system and could be used to filter out off-target energies in order to reduce the energy spread even further. By collimating the beam, the shot-to-shot spatial stability of the beam is improved by a factor of 5 measured at a distance of 1 m from the source. Additionally, by deliberately transversely offsetting a quadrupole lens, the electron beam can be steered in any direction by several mrad. These methods can be implemented while still maintaining the ultrashort bunch duration and low emittance of the beam and, except for undesired electron energies in the energy filter, without any loss of charge. This reliable and compact control of laser-wakefield accelerated electron beams is independent of the accelerator itself, allowing immediate application of currently available beams.