Laser-plasma accelerators (LPA) deliver relativistic electron beams with high peak current and low emittance, with energies up to the GeV-level in only few centimetres. However, the divergence and the energy spread of these beams remain too large for potential light source applications. A magnetic transfer line can be used to manipulate the electron beam phase-space and select the transmitted energies with a slit located at its center. We will show that with a proper focusing optics along the line, one can tune the energy spread of the beam at a given energy without loss and produce undulator radiation with controlled bandwidth. We present analytic studies, numerical simulations and experimental results on the controled electron beam transport and application to undulator radiation with a control of the bandwidth.

中文翻译：

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磁锥中激光等离子体加速电子束的能量扩散调谐

激光等离子体加速器（LPA）发射相对论性的电子束，具有高峰值电流和低发射率，能量仅在几厘米内达到GeV级。但是，对于潜在的光源应用，这些光束的发散和能量散布仍然太大。磁传输线可用于操纵电子束的相空间，并通过位于其中心的狭缝来选择传输的能量。我们将展示出，通过沿线使用适当的聚焦光学器件，可以以给定的能量调整光束的能量分布而不会造成损失，并产生具有受控带宽的波状辐射。我们目前在受控的电子束传输中的分析研究，数值模拟和实验结果，以及在带宽控制下在波荡器辐射中的应用。