论文标题
激光驱动正电子束的非侵入性表征
Non-invasive characterisation of a laser-driven positron beam
论文作者
论文摘要
我们报告了一种间接和非侵入性方法，以同时表征能量依赖性的发射率和源大小，这在通过高Z转换器目标的激光器 - 沃基加速电子束传播过程中产生的超偏好正电子束的超相对性正电子束。正上音的几何发射率与散射电子的几何散发量的很强相关性，可以通过监测后者来推断前者，以高度准确地推断出前者。该技术已在原始实验中进行了测试，其中100 meV上的正上音，我们推断出$ε_{e^+} \ $ 3 $ 3 $μm和$ d_ {e^+} \ $ 150 $ 150 $ m $ m $ $ $ $ m $ m $ m $ $ m $ m $ $ m $ m $ $ m $ m $ $ m $ m $ m $ m $ $ m $ $ m $ m $ $ m $ $ m $ $ m $ $ m $ $ m $ $ m $ $ m $。这与在GEV水平上达到亚$ $ M $ M $ M $ M $ M的几何发射量和微米级源量的可能性一致。
We report on an indirect and non-invasive method to simultaneously characterise the energy-dependent emittance and source size of ultra-relativistic positron beams generated during the propagation of a laser-wakefield accelerated electron beam through a high-Z converter target. The strong correlation of the geometrical emittance of the positrons with that of the scattered electrons allows the former to be inferred, with high accuracy, from monitoring the latter. The technique has been tested in a proof-of-principle experiment where, for 100 MeV positrons, we infer geometrical emittances and source sizes of the order of $ε_{e^+} \approx$ 3 $μ$m and $D_{e^+} \approx$ 150 $μ$m, respectively. This is consistent with the numerically predicted possibility of achieving sub-$μ$m geometrical emittances and micron-scale source sizes at the GeV level.
